EDI CINE    NATIONAL  LIBRARY  OF  MEDICINE  NATIONAL LIBRARY OF MEDICINE     N A T I Otfl
«NOIl«N     1NIDI01W  JO  llVlill 1VNOI1VN   1NOIC-3W JO AIVIIII 1YNOI1VN     IN 13 10^,
 
,Y OF MEDIC.NE NATIONAL LIBRARY O
        \A: PS/  s
F MEDICINE N«IIOH»lUI«»IT OFMIDICIH1  Nl
^Y OF MED.CINE  N A T I O N A L L I B R A R Y O F M E D I C . N E N A T I O N A L L I B R A R Y O F M E D I C I N E  N

ARY OF MEDICINE N A T I O N A I L I B R A R Y O F M E D I C I N E N A T I O N A I L I B R A R Y O F M E D I C I N E  |v
IARY OF MEDICINE  NATIONAL LIBRARY OF MEDICINE NATIONAL LIBRARY OF MEDICINE
• VBBI1 IVNOUVN  3NI3I03W JO A»V »HI 1 IVNOUVN 3NI3IQ3W JO A.VBBI1 IVNOUVN

&\ /   !  \
 
 

INTRODUCTION
STUDY   OF  HUMAN   ANATOMY.

               By JAMES PAXTON,

MEMBER OF THE ROYAL COLLEGE OF SURGEONS, HONORARY MEMBER OF THE
   ASHMOLEAN SOCIETY, AND AUTHOR OF NOTES AND ILLUSTRATIONS
              TO PALEY'S NATURAL THEOLOGY.

        IN TWO VOLUMES, WITH ILLUSTRATIONS.
VOLUME  I.
    THIRD  AMERICAN EDITION, WITH ADDITIONS,

           Bv WINSLOW LEWIS, Jr. M. D.

DEMONSTRATOR OF ANATOMY TO THE MEDICAL DEPARTMENT OF HAKVARD
                     UNIVERSITY.
         BOSTON:
WILLIAM  D. TICKNOR,
    Comer of Washington and School Streets.
          M DCCC XI..      I 7 *"/  0
.^■■GM'^
W ,.
— j. *•j . 


  Entered according to Act of Congress, in the year 1835,
          By William D. Ticknor,
In the Clerk's Office of the District Court of Massachusetts.
as
?3
42^
       boston:
isaac. r. butts, printer,
      No. 2 School Street. 
PREFACE  OF THE  AMERICAN EDITOR.
  The evident utility  of the  anatomical  work of
Paxton, founded  on the union of  graphic and ex-
planatory  designs, must at once  be apparent to
those, who, without such a guide, have experienced
great difficulties in conceiving of  the appearances
of parts from  verbal description alone.   The only
work on  Anatomy  re-published  in this  country,
accompanied with plates, is that of Charles  and
John Bell, which are  expensive, without being
well done, and the student is  obliged to turn from
the  book of the text to that of the  plates.   In these
volumes of  Paxton, at a moderate cost, this  is
obviated.   The  reader has,  at a coup deceit,  the
representation  of the part before  him, with a sim-
ple  explanation.   This  work  only  claims  to be of
an  elementary character, and one  to be studied at
the  very commencement of professional reading:
to serve to  introduce  the student to those more
elaborate  and excellent  systems,  with which  our
own anatomists have enriched this department___ 
VI
PREFACE.
   Those who are familiar with the admirable work
of J. Cloquet, Anatomie de V Homme, will perceive
that frequent use has  been  made  of it, both  in
figures and description.
  Much interest has of late been  excited by publi-
cations which display the mechanism of nature ;  in-
deed, the utility and application of animal mechan-
ics, in several branches of science beside those  of
medicine and surgery, have been frequently pointed
out.  From  the  structure and functions of living
bodies, writers on Natural Theology find ample ma-
terials for showing design and goodness in the crea-
tion ;  and certainly no ground of argument could be
better chosen, or afford more striking illustrations
of the wisdom and power  of the  Creator, than the
anatomy of man; which, throughout, is but the his-
tory of means adapted to certain ends.   Those only
who study the structure of  animated nature,  can
estimate and  admire  as they  ought  the wonderful
contrivances  of the  human frame.  " It is evident,
therefore, that the more correctly a divine is inform-
ed  respecting anatomy and  physiology, the  more
effectually will he  be enabled to employ his know-
ledge as an argument in favor of natural religion."*
And, as a branch  of general  education also, it de-
serves the attention of all those concerned in the
instruction of youth.
  It is acknowledged by most persons, that natural
history cannot be  advantageously studied unless
* Dr. Macartney. 
PREFACE.
Vll
we are acquainted with the structure of the objects
of our research, or  with comparative anatomy, so
called from its comparing the anatomy of other  liv-
ing creatures with that of man.  So, also, the science
of geology, which in the present age so much enga-
ges the  attention of philosophic inquiry, receives
great elucidation from the anatomical character of
animals.
   Natural philosophy has derived stid from the inves-
tigation of the human structure, particularly from a
knowledge of the formation of the eye and the ear;
for " the eye is  an organ or  instrument by which
vision is  performed: it is by its nature the most per-
fect  optical  instrument, and  the foundation of all
others"*
   The provisions in the eyes of different animals for
regulating the admission  of light, the adaptation of
their refracting powers to the different media, and
the momentary changes in their forms for the vision
of near or distant objects, are some of the most in-
teresting points  of  physiology, and evidently  con-
nected with the science of optics.
   The  organ of hearing may be said to be com-
pletely  artificial, differing in  different animals  ac-
cording to the circumstances in  which the function
is to be exercised.   All these  varieties are founded
on the general laws  for the  transmission of sound
through  various  vibrating substances; those laws,
therefore, cannot fail to derive  elucidation  from a
knowledge of the mechanism of the ear.
* Emerson. 
viii
PREFACE.
   In the fine arts, sculpture  and painting receive
 considerable assistance from a knowledge of anato-
 my.  Without some acquaintance with this science,
 the  artist cannot  determine  the correctness of his
 figures;  for the bones give the form and the propor-
 tion of the  joints, and the muscles  the intervening
 outline.  The various emotions of the mind naturally
 call into  action certain muscles ;  and  the  predomi-
 nating passion stamps upon the countenance a cor-
 responding  indelible impression, though  the  mind
 may not be at every instant under its  influence.
 The representation of muscular actions constitutes
 the anatomy of  expression;  so that the success  of
 the historical painter must very much depend on his
 knowing the separate and combined action of the
 moving powers, in the various  attitudes and positions
 of the human body;  for not only the face, but every
 other part of the person,  participates in the mental
 emotion, and more or less influences the  contour and
 general  character of the  figure.   Many of the an-
 cient statues, as the Laocoon,  the Gladiator,  and
 others, display a studied  observation and  a correct
 expression of muscular action.
  As a branch  of general education, anatomy  and
 physiology are subservient to  several other objects.
 For instance — in many  judicial inquiries; in the
 examination  of  legal evidence;  in  the regulation
 and infliction of punishments;  and in the considera-
tion of the best modes of coercion, or the  restraints
 which are most effectual in preventing crime ;—the
 powers of the human constitution should be accu-
 rately considered. 
PREFACE.
IX
   I have taken a  cursory view of some of  the col-
lateral advantages which may accrue from the study
of anatomy and physiology;  but to the student  in
medicine,  these sciences must be considered indis-
pensable.   Not only  is it  his duty, before entering
into practice, to obtain the most perfect knowledge
of this department of his profession, by  studying
the structure and functions of animal bodies, but he
must carefully, during the  whole course of  his pro-
fessional career, keep up his stock of information.
On the importance of anatomical science, the late
Dr. Baillie has thus expressed himself: "There is
not a physician, or surgeon, who can conscientiously
discharge his duty to  his patient or to himself, who
does not occasionally, 1 ought to say,  who does not
frequently, inspect the human frame ;  a knowledge
of which is the very foundation of medical science,
and  a guide to us in the distribution of life and
health to our fellow-creatures."
  From  an acquaintance  with the  structure and
functions  of the  several parts of the human body
when  in health, we  are able, for the most part, to
judge of its state when under deviations occasioned
by disease, and thus  to act upon  just and rational
principles in the treatment  of the  innumerable de-
rangements to which our frame is liable.   It is in
the pages of death that we  read the  history of life
— it is by  taking to  pieces the machine  that we
discover some at least of the wheels which put  it
in motion: for  the same reason we are obliged to
    VOL. I.            B 
X
PREFACE.
 examine the body by dissection, before we can ex-
 plain its constitution and  actions.   The anatomist,
 therefore,  first  studies the  apparently  simple  ele-
 ments which compose our complex fabric, examin-
 ing successively all those solid  pieces of framework
 which give to the  body its proportions, permit or
 limit its movements ; that by  separating the levers
 of the  system, he may be  better able to observe
 their junctures, and the fastenings  which  retained
 them in their situation.   Next  he traces out the
 moving powers which act on them and direct them,
 or which enable  the animated form to execute the
 external and internal actions necessary to existence.
 He then dissects  the principal tubes which distribute
 that vital and regenerating fluid, which  repairs the
 waste of  material, by supplying an  accession of
 substance to the complicated machine.   Afterwards
 he investigates  those organs  which communicate
 sensation, and transmit, swifter than lightning,  the
 orders of the will, by means of those delicate fibres
 which establish  such  intimate  relations  between
 us and the  bodies with which we  are surrounded.
 Lastly,  he analyses those  optical, acoustic, and
 chemical instruments of nature, which produce sen-
 sations; and contemplates, in  their defunct  state,
 those organs which,  under a living principle,  exer-
 cised a series of functions, excelling each other in
 the wonder they  excite, and  following one another
in such intimate succession, as  gives them  the ap-
 pearance of being connected together by an invisible
but most admirable chain. 
CONTENTS.
     ARTICLE  1.

OSSEOUS    SYSTEM.

       CHAPTER   I.
Of the Bones in General, or Osseous System,
  Ossification,   ......
  Eminences and depressions of bones,
  Forms of bones,       .....
  Color of bones,     .....
  Texture of bones,      .....
  Periosteum,       .....
  Composition of bones,   .....
  Table of the bones,       ....
  A front view of the male skeleton,
  A back view of the male skeleton,
                        CHAPTER II.

Bones of the Head,
  The sutures,      ....
  The frontal bone.  Osfrontis,
  The parietal bones.  Ossa parietalia,
  The occipital bone.  Os occipitis,
  The temporal bones.  Ossa temporum,  .
  The sphenoid bone.  Os sphenoides,   .
  The ethmoid bone.   Os ethmoides, 
Xll
CONTENTS.
                                                             Page.
The Wormian, or triangular bones. Ossa Wormiana, ossa triquetra,   29
The bones of the face,        .       .      .      .       .      .30
The nasal bones.  Ossa nasi,    .....      30
The lachrymal bones.  Ossa lachrymalia,   .      .       .      .31
The cheek bones.   Ossa malarum,     ....      31
The upper jaw bones.  Ossa maxillaria superiora,  .       .      .32
The palatine bones.  Ossa palatina,    ....      33
The turbinated bones.  Ossa turbinata,     .      .       .      .34
The vomer,       .......      35
The lower jaw.  Os maxillare inferius,      .      .       .      .36
CHAPTER  III.
The Bones of the Trunk,
  The vertebra? of the neck,
  The peculiarities of the vertebras of the neck,
  The first vertebra, or atlas,
  The second vertebra, or dentata,
  The seventh vertebra of the neck,
  The vertebras of the back,
  The vertebrae of the loins,
  General observations on the spine,
  The ribs.  Costa,
  The first rib,   ....
  The eleventh and twelfth  ribs,
  The breast bone,
  The bones of the pelvis,
  The unnamed bones.   Ossa innominata,
  The os sacrum,
  The coccyx.  Os coccygis,
 37
 38
 39
 39
 40
 41
 41
 42
 43
 44
 45
46
46
43
48
 51
52
CHAPTER  IV.
The Bones of the Upper Extremity,
  The collar bone.   Clavicula,
  The shoulder blade.  Scapula,
  The upper arm bone.   Os brachii,
  The bones of the fore-arm,
  The ulna or larger bone of the fore-arm,
52
52
53
56
57 
CONTENTS.
The radius,      .
The bones of the hand,
The bones of the wrist.   Carpus,
The bones of the palm of the hand.  Metacarpus,
The bones of the fingers.  Phalanges digitorum,
The bones of the thumb,
                        CHAPTER  V.

The Bones of the Lower Extremity,
  The thigh bone.   Osfemoris,
  The knee pan.  Patella,
  The shin bone.  Tibia,
  The splint bone.   Fibula,
  The bones of the foot,
  The bones of the tarsus,
  The astragalus,       .      .      .
  The heel bone.   Os calcis,
  The scaphoid, or navicular bone,     ,
  The cuneiform bones,
  The inner cuneiform bone,
  The middle cuneiform bone,
  The outer cuneiform bone,
  The cuboid bone.   Os cuboides,
  The metatarsal bones,
  The bones of the toes,
The Sesamoid Bones,
The Tongue  Bone.   Os hyoides,
                        CHAPTER  VI

The Teeth,    ....
  The structure of the teeth,
  The enamel of the teeth,     .      .
  The osseous substance of the teeth,
  The classes of teeth,
  The incisors,     ....
  The canine teeth,
  The grinders,     .... 
XIV
CONTENTS.
  Of the formation of the teeth,  .
  Of the deciduous teeth,   ....
  Of the permanent'teeth,      ...


                    CHAPTER  VII.

The Medullary  System or Marrow of Bones,
                  ARTICLE  II.

            CARTILAGINOUS   SYSTEM.

                     CHAPTER  I.

Cartilaginous System, or the Gristle of Bones, etc.
                 ARTICLE   III

                   FIBROUS SYSTEM.

                     CHAPTER  I.

Fibrous System,     ....


                     CHAPTER II.

Perichondrium,       ....


                    CHAPTER III.

The Ligaments,     ....
  Capsular ligaments,     ....
  Lateral ligaments,    ....
  Ligaments within the joints,     .     .      . 
CONTENTS.
CHAPTER   IV.
Particular Ligaments,  .
Ligaments of the Head,
  Ligaments of the lower jaw,
  Capsular ligament,
  Interarticular cartilage,
  Internal lateral ligament,
  •Stylo-maxillary ligament,
  External lateral ligament,
Ligaments connecting the Head  and  Neck
  Two capsular ligaments,  .
  Anterior perpendicular ligament,
  Posterior perpendicular ligament,
  Two lateral ligaments,
CHAPTER  V.
Ligaments of the Vertebrje,
  Ligaments of the second vertebra,
  Transverse ligament,
  Ligaments common to all the vertebras,
  Anterior common ligament,
  Posterior common ligament,  .      .
  Intervertebral ligament,
  Ligamenta subflava,   .
  Interspinous ligaments,  .
  Supraspinous ligaments,
  Ligaments of the oblique processes,
CHAPTER   VI.
Ligaments of the Thorax,
Ligaments of the Ribs with  the Vertebrje,
  Capsular ligaments,   .....
  Interarticular ligament,  ....
  Middle transverse ligament,  ....
  Inferior transverse ligament, 
XVI
CONTENTS.
  Anterior, or radiated ligament,      .
Ligaments of the Cartilages of  the Ribs  with  the
      Sternum,        •
Tage.
 104

 106
CHAPTER  VII.
Ligaments  of the Pelvis,
  Long posterior ligament of the ilium,
  Short posterior ligament,
  Posterior lateral ligament,
  Great sacro-sciatic ligament,
  Smaller sacro-sciatic ligament,  .
  Superior ilio-lumbar ligament,
  Inferior ilio-lumbaf ligament,
  Ilio-sacral ligaments,
  Symphysis  of the ossa pubis,
  Membrane  of the thyroid foramen,
  Ligament of Fallopius, or Poupart,
107
107
107
108
108
109
109
109
110
110
110
110
CHAPTER   VIII.
Ligaments of the  Superior Extremities,  .
  Ligaments of the clavicle,
  Interclavicular ligament,    ....
  Sterno-clavicular ligament,
  Interarticular cartilage,      ....
  Costo-clavicular ligament,
  Acromio-clavicular ligament,
  Coraco-clavicular ligament,
  Ligament of the scapula.  Acromio-coracoid ligament,
  Coracoid ligament,      ....
  Ligaments between the scapula and humerus.  Capsular ligament,
  Accessory ligament,  ..■...,
  Ligaments between the humerus and bones of the arm.   Capsular
       ligament,  .......
  External lateral ligament,    ......
  Internal lateral ligament,       .....
Ill
111
111
112
112
112
113
113
113
113
114
114

115
116
116 
CONTENTS.
XV11
Superior  articulation.
 Ligaments between the radius and ulna
       Orbicular ligament,   .
 Anterior and posterior accessory ligaments,
 Middle articulation.  Round ligament.   Chorda transversalis cu
       biti,
 Interosseous ligament,       ...
 Inferior articulation.  Interarticular cartilage.   Cartilago inter
       media triangularis,   .
 Capsular or sacciform ligament,  .
 External lateral ligament,
 Internal lateral ligament,
 Ligaments of the carpus,
 Ligaments of the first row of the carpal bones,
 Ligaments of the second row of the carpal bones
 Ligaments of the two rows of carpal bones,
 The annular ligament of the carpus,
Ligaments of the hand,   .
 Capsular ligaments,  .
 Superior transverse ligaments,   .
 Inferior transverse ligaments,
Ligaments of the fingers,
Page.

 117
 117

 117
 118

 118
 118
 118
 119
 119
 11JJ
 120
 120
 120
 121
 121
 121
 121
 122
CHAPTER  IX.
 Ligaments of the Inferior Extremities,
 Ilio-femoral ligaments,
 Cotyloid ligament,
 Capsular ligament,
 Interarticular ligament.   Ligamentum teres,
 Ligaments of the knee joint,
 Capsular ligament,
 Lateral ligaments,
 External lateral ligament,
 Internal lateral ligament,
 Crucial ligaments,
 Anterior crucial ligament,
 Posterior crucial ligament,  .
Interarticular, or semilunar cartilage,
Ligaments between the tibia and fibula,
 VOL.  I.                      r.
 123
 123
 123
 124
 125
 125
 125
 127
 127
 127
 128
 128
128
129
129 
XV111
CONTENTS.
Capsular ligament,       ....
Interosseous ligament,      ....
Ligaments of the lower end of the tibia and fibula,
Ligaments of the ankle joint,
Ligaments between the fibula and tarsus,
Ligaments between the tibia and tarsus,
Deltoid or tibio-tarsal ligament,   .
Capsular ligament,   .....
Ligaments of the tarsus,  ....
Ligaments between the os calcis and astragalus,
Ligaments between the astragalus and os naviculare,
Ligaments between the os calcis and os naviculare,
Ligaments between the os calcis and os  cuboides,
Ligaments between the navicular and cuboid bones,
Ligaments between the navicular and cuneiform bones,
Ligaments between the cuneiform bones,
Ligaments between the cuboid and external cuneiform bones,
Ligaments of the tarsus with the metatarsus,
Ligaments of the metatarsal bones with each other,
Ligaments of the metatarsus with the phalanges of the toes,
Ligaments of the phalanges of the toes,  .
Page.
 130
 130
 130
 131
 131
 131
 131
 132
 132
 133
 133
 134
 134
 134
 135
 135
 135
 135
 136
 136
 136
ARTICLE   IV.
MUSCULAR   SYSTEM
CHAPTER  I.
Muscular System, . . . . .	138
Form of the muscles, ....	. 141
The long muscles, .....	141
The wide muscles, .....	142
The short muscles, .....	142
Voluntary, involuntary, and mixed muscles,	. 143
Texture of muscles, .....	144
Cellular tissue of muscles, ....	. 145
Blood-vessels of muscles, ....	146
Nerves of muscles, .....	. 147
 
CONTENTS.
XIX
Tendons of muscles, .
Aponeuroses,
Chemical"composition of muscles,
Sheaths of tendons,
Strength of muscles,
Actions of muscles,
Nomenclature of the muscles,
Classification of the'muscles,
Page.
 147
 148
 148
 149
 150
 151
 151
 152
CHAPTER  II.
Table of the Muscles,  .
  Muscles of the head,
  ------of the face, .
  ------of the neck,
  ------of the trunk,
  ------of the abdomen, .
  .______of the posterior part of the trunk,
          of the extremities,
---of the superior extremities,
---of the shoulder, .
---of the arm, .
---of the fore-arm, .
---of the hand,
---of the inferior extremities,
---of the haunch and thigh,
---of the leg,
---of the foot,  .
Muscles of  the Head.  Cranial region
  Occipito-frontalis,
  Auricular region,
        Attollens auris,
        Attrahens auris,   .
        Retrahens auris,
Muscles of  the Face,
  Palpebral region,
        Orbicularis palpebrarum, .
        Corrugator supercilii,
        Levator palpebras superioris,
153
153
153
154
154
155
155
156
156
156
156
156
157
157
157
158
158
159
159
160
160
160
160
161
161
161
161
162 
XX                         CONTENTS.
Ocular region,
       Rectus superior,  .
       Rectus inferior,
       Rectus internus,  .
       Rectus externus,
       Obliquus superior,
       Obliquus inferior,
Nasal region,    ....
       Pyramidalis  nasi,
       Compressor nasi,  .
       Levator labii superioris alaeque nasi,
       Depressor alas nasi,
Superior maxillary  region,  .
       Levator labii superioris,
       Levator anguli oris,  .
       Zygomaticus major,
       Zygomaticus minor,  .
       Orbicularis oris,
Inferior maxillary region,
       Depressor anguli oris,
       Depressor labii inferioris,
       Buccinator,
       Levator menti,
       Masseter, ....
Temporo-maxillary region,  .
       Temporalis,
Pterygo-maxillary region,
       Pterygoideus externus,
       Pterygoideus internus,
Lingual region,  ....
       Hyo-glossus,  .
       Genio-glossus,
       Stylo-glossus  .
       Lingualis, ....
Palatine region,
       Circumflexus palati,
       Levator palati,
       Levator uvula;,
       Palato-pharyngeus,
       Constrictor isthmi faucium, 
CONTENTS.
XXI
CHAPTER  III.
Muscles of the Neck,
  Anterior cervical region,
        Platysma-myoides,
        Sterno-cleido mastoideus, .
        Digastricus,  .
        Stylo-hyoideus,
        Mylo-hyoideus,
        Genio-hyoideus,
  Inferior hyoid region,
        Omo-hyoideus,
        Sterno-hyoideus,
        Sterno-thyroideus,
        Thyro-hyoideus,
  Pharyngeal region,
        Constrictor pharyngis inferior.
        Constrictor pharyngis medius,
        Constrictor pharyngis superior,
        Stylo-pharyngeus,
  Deep cervical region,
        Rectus capitis anticus major,
        Rectus capitis anticus minor,
        Longus colli,
  Lateral cervical region,
        Scalenus anticus,  .
       • Scalenus posticus,
        Rt   us capitis lateralis,
Page.
 181
 181
 181
 182
 183
 183
 184
 184
 185
 185
 186
 186
 187
 188
 188
 189
 189
 191
 191
 191
 192
 193
 193
 193
 194
 194
CHAPTER  IV.
Muscles o* the Trunk,
  Anterior thoracic region,
        Pectoralis major,
        Pectoralis minor,  .
        Subclavius,
195
195
195
197
198 
XXII
CONTENTS.
Lateral thoracic region,
       Serratus magnus, ,
Intercostal region,
       Intercostales externi,
       Intercostales interni,
       Levatorcs costarum,
       Triangularis sterni,
Region of the diaphragm,
       Diaphragm,
Abdominal region,
       Obliquus abdominis externus
       Obliquus abdominis internus,
       Transversalis abdominis,
       Rectus abdominis,
       Pyramidalis,  .
Lumbar region,  .
       Psoas magnus,
       Psoas parvus,
       Iliacus internus,
       Quadratus lumborum,
Anal region,
       Levator ani,
       Coccygeus,
       Sphincter ani,
Genital region in the male,  .
       Cremaster,
       Ischic-cavernosus,
       Bulbo-cavernosus,
       Transversus perinaei.  .
Genital region in the female,
       Ischio-cavernosus,
       Constrictor vaginas,
Lumbo-dorsal region,
       Trapezius,
       Latissimus dorsi,
Dorso-cervical region,
       Rhomboideus,
       Levator scapulas,  .
       Serratus posticus superior,
       Serratus posticus inferior,
       Splenius,
       Complexus,
       Trachelo-mastoideus,  . 
CONTENTS.
XX111
Posterior occipito-cervical region,
      Rectus capitis posticus major,
      Rectus capitis posticus minor,
      Obliquus capitis superior, .
      Obliquus capitis inferior,
      Interspinales cervicis,
Vertebral region,
      Longissimus dorsi,
      Sacro-lumbalis,
      Transversalis colli,
      Multifidus spinas,
      Intertransversales colli,
      Intertransversales lumborum,
CHAPTER  V.
Muscles of the Extremities
Muscles of the Superior Extremity
Muscles of the Shoulder,
  Posterior scapular region,
        Supra-spinatus,
        Infra-spinatus,
        Teres minor,  .
        Teres major,
  Anterior scapular region,
        Subscapularis,
  External scapular region,
        Deltoides, .
Muscles of the Arm,    .
  Anterior brachial region,
        Coraco-brachialis,
        Biceps flexor  cubiti,
        Brachialis internus,
        Triceps extensor cubiti,
Muscles of the Fore-Arm,
  Anterior region of the fore-arm,
        Pronator teres,
        Flexor carpi radialis,
        Palmaris longus,
        Flexor carpi ulnaris, 
xxiv
CONTENTS.
        Flexor digitorum sublimis vel perforates,
  Anterior deep region of the fore-arm,
        Flexor digitorum profundus vel perforans,
        Flexor longus pollicis manus,
        Pronator quadratus,
  Posterior superficial region of the fore-arm, .
        Extensor digitorum communis,
        Extensor proprius minimi digiti,
        Extensor carpi ulnaris,
        Anconeus,    ....
  Posterior deep region of the fore-arm,
        Extensor ossis metacarpi pollicis,    .
        Extensor primi internodii pollicis manus
        Extensor secundi internodii pollicis manus
        Indicator,  ....
  Radial region,       ....
         Supinator radii longus,
         Supinator radii brevis,
        Extensor carpi radialis longior, or radialis externus longior,
        Extensor carpi radialis brevior, or radialis externus brevior,
Muscles of  the  Hand,
  External palmar region,
         Abductor brevis pollicis manus,  .
         Opponens pollicis,
        Flexor brevis pollicis manus,
        Adductor pollicis manus,
  Internal palmar region,  .
        Palmaris brevis,
        Abductor minimi digiti,
        Flexor proprius minimi digiti,
        Adductor ossis metacarpi minimi digiti,
  Middle  palmar region,
        Lumbricales,
        Interossei,     ....
             1. Abductor indicis,  .
             2. Adductor indicis,
             3. Abductor digiti medii,
             4. Adductor digiti medii,
             5. Abductor digiti annularis,
             6. Adductor digiti annularis,
             7. Abductor minimi digiti,
The Enveloping  Aponeurosis of the Upper Extremity, 
CONTENTS.
XXV
CHAPTER  VI.
Muscles of the  inferior Extremity,
  Region of the hip,
Muscles of  the  Haunch  and Thigh,
        Gluteus maximus,
        Gluteus medius,
        Gluteus minimus, .
  Pelvi-trochanteric region,
        Pyriformis,       .
        Obturator internus,
        Obturator externus,
        Gemellus superior,  .
        Gemellus inferior, .
        Quadratus femoris,
  Anterior femoral region, .
        Sartorius,     ....
        Rectus Femoris,   .
        Triceps extensor  cruris; vastus externus, vastus internus
            crurasus, .
  Internal femoral region,  .
        Pectineus,
        Gracilis,
        Adductors of the  thigh,
        Adductor longus,  .
        Adductor brevis,
        Adductor magnus,
  Posterior femoral region,
        Biceps femoris,
        Semitendinosus,
        Semimembranosus,
        Tensor vaginae femoris,
        Aponeurosis of the thigh, .
Muscles of the  Leg,
  Anterior region of the leg,
        Tibialis anticus,
        Peroneus tertius,   .
        Extensor longus digitorum pedis,
        Extensor proprius pollicis pedis,
VOL. I.
D 
xxvi
CONTENTS.
  Peroneal region,  ....
        Peroneus longus,
        Peroneus brevis,   .
  Posterior region of the leg,   .
        Gastrocnemius externus et internus,
        Soleus,
        Plantaris,  .
        Popliteus,
        Flexor longus digitorum pedis,
        Flexor longus pollicis pedis,  .
        Tibialis posticus,   .
Muscles  of the Foot,
  Dorsal region,
        Extensor brevis digitorum pedis,
        Interossei externi,
  Plantar region,
        Flexor brevis digitorum pedis,
        Abductor pollicis pedis,
        Abductor minimi digiti pedis,
        Flexor digitorum accessorius,
        Lumbricales pedis,
        Flexor brevis pollicis pedis,  .
        Adductor pollicis pedis,
        Flexor brevis minimi digiti pedis,
        Transversus pedis,
        Interossei interni,
        Aponeurosis of the leg,
        Annular ligament of the instep,
Observations on  the  Muscles,
Bursje Mucosje or Mucous Bags, 
CONTENTS.
xxvn
ARTICLE   V
VASCULAR   SYSTEM
CHAPTER  I.
Organs of  Circulation, .
The Heart and its Envelopes,
  The pericardium,
  The blood,
  The heart,    ....
        The right side of the heart,
        The right auricle,
        The right ventricle,
        Commencement of the pulmonary artery
        The left side of the heart,
        The left auricle,
        The left ventricle,
        Organization of the heart,
        The  vessels of the heart,  .
  General observations on the heart,
  Table of the arteries,
  Of the arteries in general,
  Structure of the arteries, .
The Aorta,  ....
  The  arteries which the aorta gives off at its origin
        The  right coronary artery,
        The  left coronary artery, .
  The  arteries of the  arch of the aorta,
        Arteria innominata,
        Primitive carotid arteries,
        External carotid artery,
        Anterior branches of the external carotid artery
        Superior thyroid artery,  .
        External maxillary artery,
        Branches of the external maxillary artery
        The lingual artery,
Page.
 330
 330
 330
 332
 333
 338
 338
 339
 341
 342
 342
 343
 344
 346
 347
 349
 354
 355
 356
 356
 357
 357
 357
 358
 358
 359
 360
 360
 360
 361
 361 
xxviii
CONTENTS.
	Page.
Posterior branches of the external carotid artery,	361
Occipital artery, .....	362
The posterior auricular artery, ....	363
Internal branch of the external carotid, or inferior pharyn-	
geal artery, .....	. 363
Branches which terminate the external carotid artery, .	364
Temporal artery, .....	. 364
Internal maxillary artery, ....	365
Branches of the internal maxillary artery behind the neck	
of the condyle of the jaw, ....	366
Middle meningeal artery, ....	. 366
Inferior dental, or inferior maxillary artery,	366
Branches of the internal maxillary between the pterygoid	
muscles, ......	. 367
Posterior deep temporal branch, ....	367
Masseteric artery, .....	. 367
Pterygoid arteries, .....	367
Branches of the internal maxillary artery in the zygomatic	
fossa, ......	. 367
Buccal artery, ......	367
Anterior deep temporal artery,	. 367
Alveolar artery, ......	368
Infra-orbitar artery, .....	. 368
Branches of the internal maxillary artery in the spheno-	
maxillary fossa, .....	. 3C8
Vidian, or pterygoid artery, ....	368
Superior pharyngeal artery, ....	. 368
Superior palatine artery, .....	368
Spheno-palatine artery, ....	369
Internal carotid artery, .....	369
Ophthaln.ic artery, .....	370
The lachrymal artery, .....	370
The central artery of the retina,	370
Arteries sent off by the ophthalmic above the optic	
nerve, ......	371
The supra-orbitar artery, .....	371
The posterior ciliary arteries, .	371
The long ciliary arteries, .....	371
The superior and inferior muscular arteries, .	372
Arteries sent off by the ophthalmic in its course along the	
inside of the optic nerve, .	372
The posterior and anterior ethmoidal arteries,	372
 
CONTENTS.
xxix
       The superior and inferior palpebral arteries, .
       Branches which terminate the ophthalmic artery,
       The nasal artery,    ....
       The frontal artery,
       The communicating artery of Willis,
       The artery of the choroid plexus,
       The anterior cerebral artery,  .
       Middle cerebral artery,  .      .       .
       Subclavian artery,   ....
       Branches of the subclavian artery,
       Vertebral artery,    ....
       Basilar artery,    ....
       Inferior thyroid artery,
       Inferior branches of the subclavian artery,
       Internal mammary artery,
       Superior intercostal artery,
       External branches of the subclavian artery,  .
       Transverse cervical, or posterior scapular artery,
       Superior scapular artery,
       Posterior, or deep cervical artery,
       Axillary artery,     ....
       Branches of the axillary artery,  .       .
       Acromial artery,     ....
       Superior thoracic artery, .
       Long thoracic, or external mammary artery,
       Inferior scapular, ....
       Posterior and anterior circumflex arteries,  .
       Brachial artery,  ....
       Superior muscular branch, or deep humeral,
       The inferior muscular artery,    .  •
       The ramus  anastomaticus magnus,
       The external branches of the brachial artery,
       Branches by which the brachial artery terminates,
       The radial artery, ....
       The ulnar artery,    ....
Arteries furnished by the thoracic aorta,
       Bronchial arteries,    ....
       Oesophageal arteries,
       Posterior mediastinal arteries,
       Inferior intercostal arteries,
Arteries furnished by the abdominal aorta,  .
Page.
 372
 372
 372
 373
 373
 373
 373
 373
 374
 375
 375
 377
 378
 378
 378
 379
 379
 379
 380
 380
 380
 381
 381
 381
 381
 381
 382
 383
 384
 384
 385
 385
 386
 387
 388
 391
 391
 392
 392
 392
 393 
XXX
CONTENTS.
      The right inferior diaphragmatic artery, .
      The left inferior diaphragmatic artery,
      Cceliac  artery,    .....
      Coronary artery of the stomach,
      Hepatic artery,   ....
      Splenic artery,       ....
      Superior mesenteric artery,
      Branches which are furnished on the left side of the supe
           rior mesenteric artery,  ....
      The inferior mesenteric artery,
Arteries which are furnished laterally by the abdominal aorta,
      Surrenal arteries, .....
      Renal,  or emulgent arteries, .
      Spermatic arteries,       ...
      Lumbar arteries,     ....
The arteries which terminate  the aorta below,  .
      Middle sacral artery,-....
      Primitive iliacs,   .....
      Internal iliac, or hypogastric artery,  .
      Branches of the internal iliac artery,
      Ilio-lumbar artery,   ....
      The lateral sacral artery, ....
      Gluteal, or  posterior iliac artery,
      Umbilical artery, .....
      Vesical arteries,     ....
      Obturator artery,  .
      Middle hasmorrhoidal artery, .        .      ,
      Uterine artery,   .....
      Vaginal artery,      ....
      Ischiatic artery,   .....
      Internal pudic artery,
      External iliac artery,     ....
      The epigastric artery,
      Circumflex iliac artery,  ....
      Femoral artery,      ....
      Internal branches of the femoral artery,   .
      External pudic artery,
      External branches of the femoral artery, .
      Superficial muscular artery, .
      Anterior branches of the femoral artery, .
      Abdominal subcutaneous, or external epigastric artery, 
CONTENTS.
XXXI
                                                          Page.
Posterior branches of the femoral artery, .      .       .       413
Arteria profunda femoris, or the deep muscular artery,     .    413
Popliteal artery,  ....                     415
Branches of the popliteal artery,     ....    416
Anterior tibial artery,    .      .      .                    41g
Dorsal artery of the foot,     .....    419
Peroneal artery,  .....              420
Posterior tibial artery,       ....          421 
 
GENERAL    OBSERVATIONS.
  The science of anatomy  investigates whatever enters into
the composition of  animated beings;  and the  dissection  of
their dead bodies is the chief means of  prosecuting the study.
The anatomist isolates portions, to display them more distinct-
ly ; he injects vessels, to exhibit their course ; macerates some
parts, to unravel their intimate confonnation; dries other parts,
to preserve them for  future  reference ;  and uses various other
processes to facilitate his inquiries into the intricate  and com-
plicated machinery of the animal frame.  Anatomy, therefore,
may be said to be  the science of animal organization ;  and it
requires such an examination of the instruments of life, as shall
disclose their number,  size, situation, form, color, connexion,
texture, and functions.
  This science comprehends the  structure of organized beings
in general;  but it  is  the anatomy of man only which forms the
subject of the present Introduction.
  The anatomy of the human body explains its structure under
two different conditions:  the first  is a healthy state  of the
organs, termed special anatomy;  the second is a  diseased state
producing alterations of structure, termed morbid or pathologi-
     VOL,  I,                 E 
XXXIV           GENERAL  OBSERVATIONS.
 cal anatomy.   I confine myself to  a description of the struc-
 tures and organs of the adult in the former of these conditions'.
   The human body is composed of  solids and fluids, united in
 different proportions.  The solids give the form and consistence
 to the different parts of  our bodies, and  they consist of bones,
 ligaments, muscles, tendons, vessels, nerves, etc.   The fluids
 form the greatest part of the body, and  are the  blood, chyle,
 and all the secreted liquids, as urine,  sweat,  saliva, tears,  bile,
 k.c.   These are all  contained either in  vessels, cells, or reser-
 voirs.   When the fluids of the animal frame are separated from
 the  solids, their weight is in  the proportion of eight to ten.
 This has been ascertained by an examination of  human bodies
 found buried  in the dry sands  of  Arabia, with their fluids
 evaporated  and their solids remaining perfect;  and the fact is
 confirmed by experiments on inferior  animals.
   The anatomy of the  solids has been divided  into various
 branches, expressive of the parts referred to; as,

  Osteology,   .   A description of the bones.
  Syndesmology,  .  A description of the ligaments.
  Myology,    .    A description of the muscles.
  Splanchnology,  .  A description of the viscera.
  Adenology,   .    A description of the glands.
  Angiology,     .  A description of the structure and distribution of the
  Neurology,   .    A description of the nerves.              [vessels.
  Dermology,     .  A description of the skin.

   The description  and composition of the animal fluids come
under the head  of Physiology particularly.
   The solid  parts of the body are named organs, or  the  in-
struments by which the functions are exercised.
   These  solid  parts  of  our fabric, when minutely examined, 
GENERAL  OBSERVATIONS.
XXXV
are found to consist  ultimately of layers of minute fibres,  or
filaments, varied in  appearance and texture, according to the
use and offices of the part which they compose.
   As the different organs which constitute the body are of a
more simple or complex structure, they  are made up of one  or
more tissues or textures, which are the  original materials, per-
forming the same function, in whatever part of  the body they
exist.   Most of the organs  of the  body are composed of a
variety  of these  elementary textures, which are spread out  in
the form of membranes, collected into cords, or hollowed out
into canals; and by their diversity of combination, figure, and
color, they produce all the modifications of structure and func-
tions which different organs possess.
   Bichat, an  eminent French anatomist,  pointed out the
simple  analysis  or division  of the body into  its elementary
parts ;  and the  knowledge of these has been  of the utmost
importance in the investigation and  treatment of diseases,  as
well as  of the  greatest  convenience in  anatomical  arrange-
ment.
   The  systems  of texture  may be placed  in  the following
order:  1st, the  bony  system; 2d, the cartilaginous;  3d, the
fibrous; 4th, the muscular;  5th,  the  vascular; 6th, the ner-
vous ; 7th, the mucous ;  8th, the serous;  9th, the glandular ;
10th, the adipose; 11th, the cellular;  12th, the dermoid.
   These are  further  subdivided : as the bony  system,  into the
bony and  medullary; the  cartilaginous, including the  fibro-
cartilaginous ; the vascular  is divided into  the arterial, the
venous, and the  lymphatic, etc.   But  in  this place I wish  to 
XXXVi          GENERAL OBSERVATIONS.
take a  more  general  view  of animal  structures,  and  these
twelve divisions will comprehend the whole.
   The elementary tissues are  variously combined and propor-
tioned ;  the cellular, vascular, and nervous tissues, give origin
to a variety of compound  solids, and these solids are furnished
with the  properties suited to the place they occupy and the
offices they discharge.
   It is  difficult to  ascertain the  chemical  ingredients which
enter into the composition of the body ; but, according to our
present knowledge of animal chemistry, the inorganic elements
consist of  carbon,  azote, oxygen,  hydrogen, phosphorus, sul-
phur, iron, calcium, sodium, potassium,  etc.   These  different
chemical elements again form organic elements: as gelatin, or
what is  called animal jelly ; fibrin, or a whitish elastic  fila-
mentous substance ; albumen, a vivid transparent fluid like the
white of  an egg, coagulating by alcohol and heat; mucous, a
viscid transparent  fluid,  incapable of  coagulation;  fat, or
animal oil, a  well-known  substance, insoluble  in water, and
readily melting by the action of heat.  More particular notice,
however, of the formation and chemical composition of indi-
vidual structure will subsequently occur.*

  * For the several other chemical products, I refer the reader to Berze-
lius on Animal Chemistry.                                  » 
ANATOMY
                     OF


THE  HUMAN  BODY.
                        CHAP. I.

     OF THE BONES,  OR OSSEOUS  SYSTEM IN  GENERAL.

   The bones are the hardest parts of  animal bodies; they
are  a  firm  and  common basis, on which  the moving pow-
ers are  fixed;  they  constitute a  framework  for  protecting
the vital  organs,  as  the heart and lungs, or  form complete
cases where the more  delicate  parts  of our organization,  as the
brain and spinal marrow, are securely lodged.   They also con-
stitute a series of levers, by means of which, through the agency
of the  muscles,  locomotion  and the  various  and numerous
offices of life are performed.
   A complete assemblage of conjoined bones forms the skele-
ton ; if it be united by its natural ligaments, it  is denominated
a natural skeleton ; if by wires, it is called, though incorrectly,
an artificial  skeleton,  signifying, however, that it is artificially
articulated, which indeed is the most useful mode of connecting
bones ; for, by this means, the joints can  be moved and  exam-
ined  at pleasure ;  on the contrary,  bones united by their liga-
ments have the joints rigid and concealed.
   VOL. I.               1 
2
OSSEOUS  SYSTEM.
   The  appearance  of the skeleton is different  in different
subjects, according to the period of life and the sex:  the pres-
ent subject is  to describe its formation and particular organiza-
tion in the adult, either male or female.
   The  forms  of  the bones  are sufficiently obvious in many
parts of the body to  give the points to the outline, determining
the size, proportion,  and motions of its several members.
   The bones afford attachments to the moving powers, i. e. to
the muscles by their tendons, and also to the ligaments.

                       OSSIFICATION.
   The bones  experience many changes before they arrive to
the term of their perfection, which is not until about the twen-
tieth year.
   In the first periods, their consistence does not exceed that of
other  parts.   In four weeks they harden and appear cartilagi-
nous, their form is  perfect, and they are  covered by their pecu-
liar membrane, the periosteum.   Towards  the eighth week
their vessels commence to carry red blood, instead  of colorless
fluid, which before circulated  in  them.   It is at  this period
that the true ossification begins, departing from certain centres,
which are called  the  points  of ossification, and  these vary
according to the forms of the bones.   In  the flat  bones,  the
ossific matter is  deposited in a  radiated manner; in  the long
bones, in parallel lines.
   The larger  bones  are the first formed, with the exception of
the minutest in the body, viz.  those of the  ear.   In these, ossi-
fication  is the soonest  completed; and they exceed  all  the
others in density, and in the proportion of the hard matter of
bones which they contain.
   The use for which a bone is destined, appears to have some
influence on the degree  of rapidity with which it is formed and
developed.  Thus the jaw bones  are early matured,  as they
are so soon  in life  required  for use.   On the other hand, 
OSSEOUS  SYSTEM.
3
the sternum and coccyx are  tardily perfected, because it is
necessary that the cavities  which they help to inclose should
be  kept  in a somewhat  cartilaginous  state  until a  later
period.
   Most of the bones  are formed of  several pieces,  as  may
be more particularly observed in the long ones, which  have
their  extremities* separated  from their body by a thin parti-
tion of cartilage, and it is  some  time  before the whole is
united.
   In the skull, some  of the bones, in the  first rudiments of
ossification, display a radiated, calcareous phosphate, diverging
from  the  centre  to  the  circumference.   Unossified substance
at first occupies the interstices left between them, but subse-
quently additional  bony fibres proceed  until  the cranium  is
perfect.
   When  ossification is  completed, the bones  still continue to
undergo different changes.   The general growth in stature is
completed with the process of ossification; but increase of bulk
is still for a long time  advancing to middle age,  when the bone
is stronger and less vascular; and  the different elevations of
the surface become more prominent and marked, particularly
in individuals accustomed to  strong  exercise.   Finally, as we
advance in  years, vitality progressively decreases;  and in ex-
treme  old age the  earthy  substance predominates, and the
bones become extremely fragile.

         EMINENCES  AND DEPRESSIONS  OF BONES.

  A variety of eminences and depressions characterize a num-
ber of  the  bones.   The eminences are  all those projections,
prolongations, or productions, observable on their surfaces;  and
different names have been assigned to these, derived from their
figure, situation, and use.
* Termed epiphyses and apophyses. 
4
OSSEOUS  SYSTEM.
  These eminences  are  termed  heads, when they are convex,
roundish, and smooth on their  surface.  N<c7cs, when smallest
at the middle, and gradually increasing toward the extremity.
Condyles, when the head is rather long and unequally rounded.
Tubercles or tuberosities,  when  uneven, rough and irregular.
Spines or spino is j. rocesses, when  sharp  or  pointed.   Long
elevations with sharp edges are called crista.   Such processes
as terminate in a  sharp  point  or rather edge, receive the gen-
eral name of coronoid, though most of them receive particular
names from their resemblance  to other things, as mastoid, sty-
loid, coracoid.
  Processes are  also named  from their situation, as oblique,
transverse, he.
  Some from  their  uses.   Thus two tubercles on the os femo-
ris are  designated  as  trochanters, because they serve  to turn
that bone.
  The depressions are either deep or superficial.   Of the deep
depressions or cavities, some are  termed cotylce  or cotyloid,
from their being like a cup, such as the greater cavity which
receives the head of the  femur.  Others are named alveoli or
sockets, as those in which the  teeth are lodged.
  The  more shallow or superficial cavities are called glena or
glenoid, as that part of the scapula which receives the head of
the humerus.   The cavities of the interior of bones  will be
described when considering their structure.
  These eminences and depressions are most strongly marked
in those persons who take  very  robust exercise,  and  in
the  male more than the  female, in the adult more than the
infant.
   The  eminences of articulation  are generally the expanded
extremities  of bones,  forming  surfaces  of union with  other
bones,  in which  there  are corresponding depressions.  The
mode of union varies with the form and  use of the bones thus
united ; some being immovably united, others having a limited
 or a free motion. 
OSSEOUS  SYSTEM.
5
  Muscular depressions are in proportion to the strength or ac-
tion of the muscles to which they give origin; and the degree
of projection of the eminences for insertion is always a sure sign
of the strength  of the muscles attached to them, and the energy
of their motion.  Asperities on the surface of bones in general
show where tendons or muscles are implanted.   An  extended
line usually indicates the attachment of a broad  tendon ; pro-
jecting points have tendons or ligaments corresponding.
  It may be easily conceived that the moving powers  must act
with greater advantage by being removed  farther  from the cen-
tre of the bone, by means of such projecting points.   The em-
inences for the  insertion of ligaments also afford a similar advan-
tage, by removing, in some degree, the ligament from  the artic-
ulation, thus facilitating the motion of the latter, as we may ob-
serve in the elbow and the knee.
   Eminences  and  depressions from apparent  impression, are
such as  the irregularities of the inner  surface of the skull, or
such as  muscular impressions  on  other bones present.   They
are supposed to be occasioned by the pressure of different organs
on the surface  in  their growth or actions.  If these impressions
are not actually the result of the compression of the  organs  on
the bone, they show that the bones are provided with  forms ad-
mirably accommodated to the adjacent parts.
                    FORMS OF BONES.


  Viewed in respect to form, bones have been arranged under
four  classes — the long, the broad, the short, and  the mixed
bones.
  The  first, in general,  belong to the parts of locomotion,
where they  become  levers moved  in various directions by the
muscles.  These have all a medullary canal, and their extremi- 
6                   OSSEOUS SYSTEM.
 ties are considerably larger than their bodies, and are porous and
 reticulated, which  gives  them  a greater  degree  of lightness,
 increases the articulating surfaces, and consequently diminishes
 their liability to luxation.   The body of these bones is usually
 round.   The greater  distance these are from the trunk of the
 body, the less is their volume, but the greater their number.
   The second, or broad bones, are little connected with  loco-
 motion, serving chiefly for the  insertion of muscles, which  pro-
 ceed to the long bones, and  form ordinarily by their union  the
 walls or parietes of certain cavities, as the cranium and pelvis.
 They are  nearly  equal in  length and breadth,  but vary  in
 thickness.   They have  two lamina ;  and in the  cranium  the
 internal is  thinner and harder, and  has therefore the name of
 tabula vitrea.
   The  third, the short bones,  are situated in those parts  in
 which solidity and motion  must be united, as in the spine,  the
 wrist, and the  instep, where their number  insures these  two
 properties, namely :  solidity, because the force of external  me-
 chanical shocks is  expended on  the  wide surface by which
 they  are connected ; and  mobility, because  from their  indi-
 vidual partial motions, there results collectively a very exten-
 sive general one.
   Besides these three classes of bones, there is a fourth, termed
 by Meckel mixed bones, for they seem to be formed by the union
of the bones of the other classes, chiefly of the second and third,
being composed of flat and  short portions, viz. the sphenoid,
 temporal, and ethmoid bones.
                     COLOR OF BONES.

  The color of the bones depends upon their age, or the man-
ner in which they have been prepared.  In the adult, the color
is of an opaque white, when fresh, more or  less tinged with 
OSSEOUS  SYSTEM.
7
red ; in younger subjects, however, the bones are more vascular
and colored than in those of more advanced years.
TEXTURE OF BONES.
  The texture of the bones, like every  other animal structure,
has a fibrous appearance.   The  nature  of bony fibre is every-
Fig. 1.
St*
                  where  the same, but  being differently  ar-
                  ranged admits of two essential modifications :
                  in one bone, or in part of the bone, the fibres,
                  more or less distant from each other, display
                  a profusion of cells;  in  other parts, closely
                  compressed together,  they form  a kind of
                  compact substance,  in  which they cannot
                  easily be discerned.  By sawing a cylindri-
                  cal bone in a longitudinal direction, the  ar-
                  rangement of the fibres is evident.
                    Fig. 1 is a section  of the thigh  bone; a,
                  a, the extremities, having  to some  extent a
                  shell of compact texture, crowded with small
                  cells, diminishing  in  size, but increasing in
                  number  as  they approach the  articulation.
                  They  are  named cancelli, or spongy struc-
                  ture,   c, the cavity for containing the mar-
                  row.   The hollowness  increases the  diame-
                  ter,  consequently  the comparative strength
                  of the cylinder,   b, b,  the walls or sides of
                  the shaft, very solid.    Observe,  the com-
                  pact texture  is  thicker  near  the  middle of
the bone, where  the greatest  forces are  most frequently ap-
plied.
   The short bones are almost entirely of a cellular  structure,
covered only by a thin layer of compact texture ; in this re-
spect their organization is similar to the heads of long bones. 
8
OSSEOUS  SYSTEM.
  The broad bones are usually composed of two compact plates
of a moderate thickness, having a cellular structure interposed j
but in general wherever  broad bones are thin,  and there is a
deficiency of cancelli, very powerful muscles meet, and by their
thick layers compensate for the want of solidity in the bone, as
in the occiput, ilium, scapula, etc.
                       PERIOSTEUM.

   This is a fibrous membrane, so called from its surrounding all
 the bones, and providing them with a  covering everywhere ex-
 tended over them, except in such parts as  are  tipped with car-
 tilage, and the teeth which are protected by enamel.
   The ancients had figured to themselves the periosteum as ex-
 tending from one  bone to  another over the articulations, and
 thus forming a continued bag for the whole  skeleton.  This idea
 is nearly  correct;  for although  the periosteum ceases at the
joint, it is interwoven with the ligaments that surround  the
joints ; in this manner continuity may be conceived.
   The periosteum in infancy is slightly united  to the bone, and
 is removed from it  with  the utmost facility.   In the adult  the
adhesion is more firm; it is  excessively  so in  an  aged person.
The inner surface of this membrane is firmly fixed to the bone
by numerous  vessels and  fibrous threads,  particularly  in  the
extremities of the  long bones and  on the  short  bones, which
we can easily  conceive by  the great number  of apertures  we
see in  them.   The  connexion between  the  periosteum and
the adjacent  organs is  much  varied;  for the most part the

  * In the English edition, the description of the periosteum is deferred until
the author is on the subject of Fibrous Membranes; but being so immedi-
ately connected with the Osseous System, it was considered  proper to place
it where it now is. 
OSSEOUS  SYSTEM.
9
muscles are attached to,  or glide  upon  it, and it is  more or
less united to them and to the integuments by cellular  mem-
brane.
  The  periosteum  borrows its vessels  from  those adjacent.
Their mnumerable  branches form an intricate net-work, which
is rendered very  striking by injections, especially in infants;
they are then  lost in the compact texture  of the bone,  or are
returned to the surrounding parts.
  This membrane is no doubt supplied with nerves, though so
minute  as not to  be easily demonstrated.   Like  bone  in
its  healthy or natural state,  it possesses little or no sen-
sibility ; yet  when  inflamed  its feeling  is exceedingly pain-
ful,  so that  we  cannot  but allow it to  be endowed  with
nerves.
  That absorbent  vessels  also penetrate  the periosteum,  is
argued from its restoration  from diseases.   In some cases it at-
tains an unnatural thickness, and in process of time regains its
natural  tenuity, which can  only be the  result of the action of
the  absorbents.
  The periosteum is subservient to several uses.   1st. It is the
nutrient membrane  of the bone;  it endows  its  exterior with
vitality and if it be  separated from it, the surface of  the bone
perishes.  2d. It  gives convenient insertion to nearly the whole
of the fibrous system ;  viz. the tendons, ligaments, aponeuroses
and also muscles,  are attached to this membrane. 3d. By means
of the smooth surface of the periosteum, the action of the mus-
cular fibres and the tendons  is easy, and the effects of friction
are  averted.

                  COMPOSITION OF BONES.

  The composition of bones, whatever  may be  their forms,
is the same;  it consists of a  mixture of earthy and animal
matter.
  VOL. I.                     2 
10                 OSSEOUS  SYSTEM.
  The existence of the first is proved by burning bones in fire ;
combustion, destroying the animal  matter, leaves a brittle sub-
stance, which is the earthy part, of the  same form with that of
the bone.
  The  animal part  of  bone is not less evident, for  by im-
mersion  in  a weak acid, the  earthy matter is dissolved, and
there remains a cartilaginous body, flexible and elastic, bearing
the same form as the bone.
  These two substances are the essential component parts of
bones.   The earthy is intended to provide  them  with  the
strength and solidity, that characterize them; the animal parts
endow  the bones with  the  principles of vitality, growth,  and
nutrition.
   The skeleton  consists of about two hundred and fifty-two*
bones,  which are divided into those of the head, the trunk and
the extremities;  some of them  are single,  and others  are in
pairs.   There are
	Frontal	.	- Osfrontis -	-	- 1
	Parietal	-	Ossa parietalia -	-	- 2
13	Occipital	-	- Os occipitis	■	- 1
	Temporal	-	Ossa temporum -	-	- 2
^3	Sphenoidal	-	Os sphenoides	-	- 1
	Ethmoid	-	Os ethmoides	-	- 1
*+*	Nasal	-	- Ossa nasi	-	- 2
o	Malar	-	- Ossa malarum	-	- 2
§ *	Lachrymal	-	Ossa lachrymalia	-	- 2
o	Upper jaw bones	-	Ossa maxillaria superior a		- 2
	Palate bones	-	- Ossa palatina	-	- 2
V3 i	Inferior turbinated bones		Ossa turbinata	-	- 2
					- 1
VB	Lower jaw	-	- Os maxillare inferius	-	- 1
	Teeth	-	- Denies	.	- 32
	Tongue bone	-	• Os hyoides -	-	- 1
  * The exact number of bones in the human frame is variable; the sesa-
moid bones  and ossa Wormiana are not constant;  and in reckoning the bones
of the skeleton, the small bones of the ear are usually omitted. 
OSSEOUS  SYSTEM.
11
  To these may be added the  proper bones  of the ear, con-
tained in the temporal bones :
18-• i							2
							2
CO Tlieb							2
							2
	ack bone or spine	consists of					
m^*							24
CD S3 C £	Ribs	-	-	Costce	-	-	24
	Breast bone	-	-	Sternum	-	-	2
	Hip bones	-	-	Ossa innominata	-	-	2
	Rump bone	-	-	Os sacrum	-	-	1
o	_ Coccygeal bones	-	-	Ossa coccygis	■	•	4
	Collarbones	«	.	Clavicula	-	-	2
*4-l	Blade bones	-	-	Scapula	-	-	2
o 1/3	Arm bones	-	-	Ossa humeri	-	-	2
CD S3	Fore arm bones	-	-	Radii et ulna	-	-	4
O r^2	Wrist bones	-	-	Ossa carpi	-	-	16
O £ • 1 CO	Hand bones	-	-	Ossa metacarpi	-	-	8
	Finger bones	-	-	Phalanges digitorum manus 24			
	Thumb bones -	-	-	Ossa pollicis -	-	-	6
^3 § S	Sesamoid	-	-	Ossa sesamoidea	-	-	4
S3 CD	Thigh bones	-	-	Ossa femoris	-	-	2
	Knee pans	-	-	Patella	■	-	2
	Shin bones	-	-	Tibia -	-	-	2
CD T3 -a S3	Small bone of the legs		-	Fibula	-	-	2
	Tarsal	-	-	Ossa tarsi	-	-	14
3	Metatarsal	-	-	Ossa metatarsi	-	-	10
CD	Toe bones	-	-	Phalanges digitorum		pedis	28
°	. Sesamoid	-	-	Ossa sesamoidea	-	-	4
                                                      252

  In describing the relative position, or the relation which one
part bears to another in the subsequent chapters, the  anatomist
supposes the body  erect.   By superior and inferior, is signi-
fied higher and lower with respect to the erect  position.  By
anterior and posterior is denoted the situation of  the parts  as
nearer to the fore  or hinder surface of the body ; and by later- 
12
OSSEOUS  SYSTEM.
ally is to be understood, that the parts so described approach
the one side or the other.   Inner and outer, and external and
internal, express the  relation of any given part or portion  of
the body to the middle line of the body, or to an imaginary
plane bisecting the body into  lateral halves,  passing through
the head and trunk, and continued between the lower extrem-
ities. 
 
TACT .IT.
v.*
p' 
TABLE I.
Represents  a front  view of the  male skeleton.
             HEAD AND  NECK.

 a,  The frontal bone.
 b,  The parietal bone.
 c,  The temporal bone.
 d,  A portion of the sphenoid bone.
 e,  The nasal bone.
/,  The malar, or cheek bones.
 g,  The superior maxillary, or upper jaw bone.
 h,  The lower jaw.
 i,  The bones of the neck.
a,  The twelve bones of the back.
b,  The five bones of the loins.
c, d, The breast bone, composed of two pieces.
e,f, The seven true ribs.
g,g,The five false ribs.
h,  The rump bone,  or sacrum.
i,  The hip bones.

            UPPER EXTREMITY.

o,  The collar bone.
b,  The shoulder blade.
c,  The upper arm bone.
d,  The radius.
e,  The ulna.
f,  The carpus, or wrist.
g,  The bones of the hand.
h,  The first row of finger bones.
i,  The second row of finger bones.
k,  The third row of finger bones.
I,  The bones of the thumb.

            LOWER EXTREMITY.

a,  The thigh bone.
6,  The knee pan.
c,  The tibia, or large bone of the leg.
d,  The fibula, or small bone of the leg.
e,  The heel bone.
f,  The bones of the instep.
 g, The bones of the foot.
 h,  The first row of toe bones.
 i,  The second row of toe bones.
 k,  The third row of toe bones. 
TABLE II.
Represents a  back view of the  male skeleton,


                    THE HEAD.

    a,  The parietal bone.
    b,  The occipital bone.
    c,  The temporal bone.
    d,  The cheek bone.
    e,  The lower jaw bone.

                NECK AND TRUNK.

    a,  Thebones of the neck.
    b,  The bones of the back.
    c,  The bones of the loins.
    d,  The hip bone.
    e,  The sacrum.

                UPPER EXTREMITY.

    a,  The collar bone.
    b,  The blade bone.
    c,  The upper bone of the arm.
    d,  The radius.
    e,   The ulna.
   f,   The bones of the wrist.
   g,  The bones of the hand.
   h,  The first row of finger bones.
   i,   The second row of finger bones.
   k,  The third row of finger bones.
   I,   The bones of the thumb.

               LOWER EXTREMITY.

   a,  The thigh bone.
   6,  The large bone of the leg.
   c,  The small bone of the leg.
   d,  The heel bone.
  • e,  The bones of the instep.
   /,  The bones of the toes. 
TA1B .Til.
 
 
OF THE  HEAD.
15
CHAP. II.
BONES OF THE HEAD.
   These  comprehend the bones of the  cranium and face,
which are twenty-two in number.   Some of them are in pairs,
but others are only single bones.
   In the cranium  or skull there are two  pairs and four single
bones, viz.

               2 Parietal.
               2 Temporal.
               1 Frontal.
               1 Occipital.
               1 Ethmoid.
               1 Sphenoid.

   To the face there are six pairs and two single bones, viz.

               2 Nasal.
               2 Lachrymal.
               2 Malar.
               2 Superior maxillary.
               2 Palatine.
               2 Turbinated.
               1 Vomer.
               1 Inferior maxillary.

   The cranium is the vaulted cavity for lodging the  brain, its
 membranes and vessels.
   The inner and  outer surfaces of the bones are composed  of
     Fig. 2.      compact layers, Fig. 2, a, called the  external,
                and b, the internal tables of the skull.   They
                are  not  parallel  to each  other, but in some
                places very compressed.   There is  an inter-
 mediate cellular texture, c, between them, termed diploe, which
 is similar to  the cancelli of other bones,  and it serves  a like
 
16
0SSE0U3  SYSTEM
purpose, viz. to convey vessels and nerves from one  region to
another.   The character of the two tables differs ; the external
is fibrous, the inner  exceedingly compact and brittle, so as to
obtain the name of vitreous.
                       the sutures.

   Upon the surface of the skull we observe various  lines,  di-
viding it  into different por-
tions, as in Fig. 3, the upper
part of the  skull.    These
lines are  the  joining of the
several bones  to each other,
and form  a resemblance, on
a  superficial  view,  to  the
stitches of a seam ;  they are
denominated sutures.  Their
origin is  this : the radiated
fibres  of the  bones in their
growth approach each oth-
er, the fibres of one bone en-
tering the  interval  of  the
fibres of another bone, and forming the serrated line  of union
called suture.
   a, a,   The coronal suture, has its  name  from being situa-
ted at that part of the head upon which the ancients were used
to place the laurel or  olive crown, given to the victors in  their
games.  It passes transversely over the  skull, and  joins the
frontal  with the parietal bones.
   6,  The sagittal suture, named from its straight course.  It
extends from the middle of the superior margin of the  frontal,
to the angle of the occipital bone.   It  is the union of the two
 
OF  THE  HEAD.
17
parietal bones.  This  suture  is occasionally  continued down
the frontal bone to the nose : this  part of it is then named the
frontal suture.
   c, The lambdoidal  suture, receiving  this name from its re-
semblance to the Greek A.   It commences at the termination
of  the sagittal suture, and extends on each side to the base of
the cranium.   It joins the occipital to the parietals above, and
to the temporal bones below.  There  is  great irregularity in
this suture :  it  is frequently diverted from its regular course by
the interposition of little  bones (separate ossifications),  d, d,
which, from being of a triangular  shape, have been called ossa
triquetra, or ossa  Wormiana, in  compliment  to  Olaus Wor-
mius, an anatomist, who first particularly described them.
   The superior portions of the temporal  bone are joined to the
parietal by thin, indented, yet scaly overlapping of the former,
e, c, hence named  the squamous suture.   Near  the occipital
angle it loses its squamous character, and  is simply united by
a serrated line, under  the name of additamentum sutures squa-
mosa.
   Two  other  sutures are sometimes reckoned, viz. the eth-
moidal  and the sphenoidal;   but  they unite the ethmoid and
sphenoid  bones to those adjacent, by  irregular lines,  by no
means having the character of a suture.
VOL. I.
3 
18
OSSEOUS  SYSTEM
                FRONTAL  BONE.   Os frontis.

   This bone forms the forehead, part of the  temples,  and the
roof of the orbits ; its shape has been compared to that of a clam
shell.   Fig. 4 is a front, Fig. 5 a  back view.  Two eminen-
ces, a, a, mark the  situation
of the frontal sinuses.  These
are  formed by an  apparent
separation of the  two tables
of the skull, leaving very con-
siderable cavities, which  com-
municate with the nose.*
   On  each side of the  fore-
head we  observe b,  Fig. 4,
the  temporal  arch,  at  first
strongly marked, but  less  so
as it passes upwards.   The hollow forms part of the  temporal
fossa.   In the  middle and  at the lower edge  of  this bone is c,
the nasal process, and  ethmoidal notch.  On the ridge over
which  the eye-brow is placed we observe d, a hole ; sometimes
it is only a notch  in the  bone, as on the other side of this spec-
imen, though it is there completed by  a ligament, so as to form
a hole  called the upper orbitary hole.f  The ridges just men-
tioned  terminate at e, e,  the external angular processes.   The
angles  opposite are the internal angular processes.   Between
these are/, f  the orbitar plates,  slightly concave, and have
near the outer angle a depression^ for the reception  of the lach-
rymal gland.

  * These cavities increase the intensity of the sound of the voice, and ren-
der it more melodious.
  t Foramen supra-orbitarium.  For the passage of the first  branch of the
fifth pair of nerves.
  t Fossa lachrymalis.
 
OF  THE  HEAD.
19
   On  the  internal surface,  Fig. 5, are slight  depressions,
answering to  the convolutions of the brain.   h, the  frontal
            Fig. 5.                  spine,  is  a sharp  ridge
                                   commencing at  the  eth-
                                   moidal notch and extend-
                                   ing upwards about an inch,
                                   where it divides  into two
                                   ridges  with  a  shallow
                                   groove between them, call-
                                   ed  the frontal  farrow.
                                   At the  root of the  spine
                                   at A, is a small hole, which
                                   not perforating the bone or
leading to any cavity, is called the blind hole.*   i, i, the open-
ings of the  frontal sinuses.   The  os frontis is joined above and
behind with the ossa parietalia, which junction terminates at a
line running horizontally backwards from the point of the angu-
lar process ; between those two points and behind as far as  the
ethmoidal notch, it joins with the sphenoid bone on each side;
within the ethmoidal notch it receives the ethmoid bone, which
joins to"the  orbitar plates,  at the interior part of which it unites
with the os  lachrymale ; in front it  joins its nasal process and
spine with the ossa nasi and superior maxillary bones, and by
its outer angular processes  with the  malar bones.
   The muscles attached to  the os  frontis are three pairs, viz.
the temporal muscle, the corrugator supercilii,  and orbicularis
palpebrarum, on each side.  It is also covered by the  occipito-
frontal.
* Foramen caecum. 
20
OSSEOUS  SYSTEM
the parietal bones, Ossa parietalia,
   Are a pair, forming the sides and vertex, or top of the head.
Etternally, Fig. 6, each bone is convex; and as it has  four
angles, they are denominated
according to their relative sit-
uation in the skull, the fron-
tal and temporal angles, and
the superior or inferior occi-
pital angles.   The marginal
ed^es  also are  named  from
their connexions, as a, in this
and  the  subsequent figure,
the  anterior  edge, is called
the frontal margin; b, the
parietal margin;  c,  the  occipital margin; d, the temporal
margin.  On the convex surface is a transverse arched  impres-
sion, e, which marks the attachment of the temporal muscle.
   On the internal and concave surface, Fig. 7, /, /,  are im-
pressions, or  furrows, which                Fig. 7.
are for the ramifications of the
artery of the  dura  mater, or
outer membrane of the brain.
Sometimes part of the artery
runs in a canal in  the bone,
as in  this specimen at the
temporal  angle.   Near the
superior margin there is  com-
monly a small hole, through
which a vein passes from the
integuments of the head to the longitudinal sinus.
 
OF THE  HEAD.
21
  The parietal bone is joined by its frontal edge to the os fron-
tis ; by the parietal edge to its fellow ;  by its occipital edge  to
the os  occipitis :  and  by  its temporo-splier. idai  edge to the
temporal and sphenoid bone?.
  The only muscle attached to  the  parietal bone is  the tem-
poral.
the occipital bone, Os occipitis,
Fie. 8.
  Is situated at the back part of the head, and forms part of the
base of the skull.   It is convex externally. Fig. 6 ;  concave in-
ternally, Fig. 9.
  The most remarkable parts to be noticed on the exterior, Fig.
                                8, are a, the occipital angle ;
                                b, a prominence  called the
                                tubercle,  from each  side  of
                                which  there is a transverse
                                arched ridge,* and below is
                                another ridge, following near-
                                ly the same direction.  These
                                are  to be borne in mind  as in-
                                dicating  the  attachment  of
                                some of the muscles of the
                                head.  There are also several
                                depressions, shewing  the in-
                                sertion  of muscles.   At the
under and fore part of the bone is c, the great opening,,f through
which  passes the medulla oblongata, or upper part of the spinal
marrow, its membranes, the vertebral arteries, and the spinal ac-
* Linea semicircularis, or arcus transversus.
t Foramen magnum occipitis. 
22
OSSEOUS  SYSTEM
cessory nerves ; d, the anterior condyloid holes, through which
the lingual nerves pass ; e, e, the posterior condyloid holes,  for
the passage of the veins of the neck :  frequently one or both of
the latter holes are wanting, in which case  the  veins  proceed
through the foramen magnum ; f, f the condyles or smooth em-
inences for articulating with the first bone of the neck; g, the
basilary or cuneiform process.
   The inner surface, Fig.  9, is  concave,  and divided  by a
crucial ridge,  b.   To the                 Fig. 9.
crucial ridge  are  attached                  cc
processes of the dura mater,
viz. from a to 6, a portion sep-
arating the posterior lobes of
the cerebrum ;  from b to c, a
portion dividing the cerebel-
lum ;  and from b to g each
side,  another,  which  sepa-
rates  the cerebrum from the
cerebellum.  In  this curved
ridge from b to g,  are  seen
transverse grooves, shewing
the situation of the lateral sinuses ; c, the great foramen ; e, e,
the condyles ; f, the basilary process.  The occipital bone is
united by its parietal margin to the parietal bones; by its tem-
poral to the margin of the mastoid portion of the temporal bone;
by its basilary margin to the petrous portion of the same bone;
and by its basilary process to the sphenoid bone.
   The muscles attached to  the os occipitis  are ten  pairs, viz.
the trapezii, complexi, splenii, recti postici majores, et minores
capitis, obliqui superiores capitis, recti laterales, recti interni,
majores, et minores capitis, and the single muscle occipito-fron-
talis.
 
OF  THE  HEAD.                  23
          the  temporal bones, Ossa temporum,

  Are a pair.  They are so named because they occupy the region
of the head where the hair usually commences to whiten, thus in-
dicating the period of life.  They are irregular in their form, and
unequal in their thickness. Fig. 10 is an outer view.  Each bone
is distinguished by two distinct portions :  the upper part is thin
         Fig. 10.              and  of a scaly character, hence
                             named the squamous portion ;
                             the other half of the bone is  of
                             a  triangular  form  passing  in-
                             wards  and   downwards,   and
                             being  of  a  close  texture  and
                             rocky  hardness,  is  called  the
                             petrous portion.   If a horizon-
                             tal line were drawn from b, the
                             squamous portion would be all
that part above the line.   It forms the chief part of the  tem-
ple.  The squamous  portion is bounded at its base by b, the
zygomatic process, which is  a thin  and  narrow projection of
bone ;  at its root it has c, a tubercle or eminence,  and termi-
nates in b, an indented process, which, from its union  with the
malar or cheek bone, is called the malar process.  Immediately
behind the eminence c, is a cavity for the articulation of the
lower jaw.   At the back part of this cavity is an apparent divi-
sion in the bone, the glenoid fissure, through which passes a
nerve called the corda tympani.   On  the lower surface of the
eminence just mentioned, the  jaw moves when brought  for-
wards.  At d, is a deep hole, the external auditory passage.*
From the lower  part of the bone is  a  remarkably long  and
* Meatus auditorius externus. 
24
OSSEOUS  SYSTEM
 pointed process, e, which, from having some resemblance to an
 ancient style, or iron  writing  pen, is named  styloid process.
 Several muscles are  attached  to this slender portion of bone,
 and derive their names from it.  At the root of the process, f
 is a ridge of bone termed the vaginal process, imagination hav-
 ing formed it into the likeness  of a sheath to the styloid process.
 Further behind is g, the mastoid process ;  it is a very consider-
 able prominence, the texture of which is cellular, but the cells
 are seen only in a section of the part.   There is  one or more
 holes at the  back part of this process, seen  at c, Fig.  11, called
 the mastoid  foramen or foramina.  Between the root of the
 styloid and mastoid processes,  is the stylo-mastoid foramen: it
 is the  passage for the portio dura of the seventh pair of nerves.

   Fig. 11 is the inside view.  On  the  squamous  portion we
 observe marks of the convolutions of the brain, and a, the edge
 bevelled off  where it overlaps in joining the parietal bone.   On
 the petrous  portion  is b, the
 internal  auditory passage*
 by which the nerves of hear-
 ing have access from the brain
 to the  ear.   Posterior  to this
 is a foramen, called the aque-
 duct of the cochlea :  it serves
 for the entrance and  exit  of
 the blood-vessels of the  ear.
 On the  opposite side, in the
interior part  of the petrous portion,  is a  small  hole called the
 Vidian foramen.

  * Meatus auditorius internus.  It should be observed, that this opening
 soon divides into two : the first, called the aqueduct  o/Fallopius, for that
division of the seventh pair of nerves,  the portio dura, which is distributed to
the face; the second foramen admits the other division of this nerve, the por-
tio mollis, by several small apertures,  into the  intricate passages  of the  ear,
 to become the proper organ of hearing.
 
OF  THE HEAD.
25
  Near the point, called the inferior angle, is /, the  entrance
of the carotid canal, for the passage of the chief artery of the
brain;  g, the bony part of the Eustachian tube.*   At the base
of the bone is the jugular fossa, or thimble-like depression, made
by the first turn or commencement of the jugular  vein.  The
temporal bone is united,  by its malar process, to the zygomatic
process of the os mala?; by the inferior edge  of the squamous
portion to the spinous process of the os sphenoides ; by the supe-
rior edge of the same part  to the temporo-sphenoidal  edge of
the os parietale ; by the superior edge of the  mastoid portion
to the temporal angle of that bone ;  by the inferior part of the.
mastoid portion and the petrous portion, to the temporal and bas-
ilar edges of the os occipitis, and the basilar  portion of the os
sphenoides.
   There are sixteen muscles attached  to the temporal  bone,
viz. the temporalis, masseter, retrahens auris,  occipito-fronta-
lis, sterno-cleido-mastoideus, complexus minor, splenius, digas-
tricus, stylo-hyoideus,  stylo-glossus,  stylo-pharyngeus, and  the
constrictor pharyngis  superior; and the muscles  moving  the
small bones of the ear, the  tensor tympani, laxator tympani,
externus mallei, and stapedius.
   Besides the parts which have been described, the temporal
bone contains the organ of hearing, which includes  the ossicula
auditus, etc.  As, however, these parts cannot be  understood
till several sections of the temporal bone have been made, I shall
refer the reader,  for a  further description, to the article on
the senses.

  * Iter a palato ad aurem.  It is named the Eustachian tube from Eusta-
chius, an eminent anatomist, who discovered it.
   VOL. I.            4 
26
OSSEOUS SYSTEM
                   THE SPHENOID  BONE,

                       Figs. 12 and 13,

  So called from its situation in the  base of the skull, where it
wedges in and locks together most of the other bones, for  it is
united  to fourteen distinct bones.  Its general resemblance to
a bat with extended wings, has given names to different parts
of the bone.   Fig.  12, a, the pituitary fossa or sella turcica,
a slight  concavity  in the              Fig.  12.
centre  of the bone  for the
lodgment of the pituitary
body ;  b, b, points  having
the name of the anterior,
and c,  c, the posterior cli-
noid processes,  so called
from their supposed resem-
blance to the knobs of a bedstead.   An  eminence in front, d,
is called the olive-shaped process, upon which the optic nerves
meet and unite ; e, e, the optic foramina, through which these
nerves and an artery  pass to the eye.   The points f, f,  con-
tinued from the anterior clinoid  processes,  are the transverse
processes, or the smaller wings.   In front of the  body is g, the
ethmoidal spine; h, the basilar process, which joins  the occi-
pital bone ; on  each  side of that  process is a deep notch, form-
ing part  of the carotid  foramen.   Between the transverse spi-
nous process and the temporal portion  of the bone, is i, i, the
sphenoidal  fissure or foramen  lacerum, which  transmits the
third,  fourth,  and sixth  pair of  nerves, and the first branch of
 the fifth pair; behind and below, are k, k, the round foramina,
 which transmit the second branch of the fifth pair of nerves ;  I,
 I, the  oval foramina, through which pass the third branch of
 
OF  THE HEAD.
27
Fig. 13
the fifth pair of nerves ;  m, m, the spinal foramina, by which
the middle artery of the  dura mater passes ;  n, n, the entrance
of the pterygo-palatine canals, by  which  the palatine nerves
pass to the mouth ;  o, o, the temporal portions, or  plates,  or
the larger wings ;  q, q, the spinous processes.
   In the posterior view, Fig. 13,/,/, is a profile  of the trans-
verse processes; i, i, the sphenoidal fissure; o, o, the temporal
plates, or  alae ; p, p, the smooth surfaces which constitute part
of the orbit of the eye, the orbitar plates; q, q, the spinous pro-
                                    cesses ; r, r, the external
                                    pterygoid processes ; s, s,
                                    the  internal  pterygoid
                                    processes, each of which
                                    terminates in a little curv-
                                    ed  process, called the
                                    hook like process,* over
                                    this a  tendon of the ex-
tensor muscle of  the  palate  plays  ; t, the azygos process ;  u,
the body  containing the sphenoidal cells:  the  lines point  to
their openings.
   There is a foramen  at the  base of each  pterygoid process,
called the  Vidian foramen,  from Vidius,  who  discovered  it.
This transmits a nerve that does  not go from the cavity of the
cranium, but returns into it.  The  second branch of  the fifth
pair, after passing out of the cranium, sends  back, through this
foramen, a branch called the Vidian, which, upon its arrival in
the cranium, enters the temporal bone.
   The sphenoid bone  is united by its ethmoidal spine to the
nasal plate of the os ethmoides ; by its transverse process and
the orbitar plates to the os  frontis ;  and at  the back part of  its
temporal to the sphenoidal angles of the ossa parietalia ; by the
posterior edges of  the  same plates, and its spinous process, it
* Hamular process. 
28
OSSEOUS  SYSTEM
joins the squamous portions of the temporal bones.   From its
spinous  processes to the  roots of the  pterygoid processes, it
touches the inferior angles of the  petrous  portions of the tem-
poral bones ;  and by its basilar process it is connected with the
sphenoidal process of the os occipitis : by the  anterior edges of
its orbitar plates it is united to the ossa malarum ;  by the ante-
rior  surfaces of its pterygoid plates to the ossa palati; and by
the  azygos process to the vomer.
  There are thirteen pairs of  muscles attached to the os sphe-
noides ; viz. the levator palpebra superioris, the recti muscles
of the eyes, the superior oblique muscles of the eyes ; the tem-
poral and pterygoid muscles, buccinator, externus mallei, con-
strictor pharyngis superior and tensor palati.


            the  ethmoid bone.   Osethmoides.

  Fig.  14, a  side view; Fig. 15, a posterior; Fig. 16, an
anterior view.   The  letters refer  ' to the  same  parts in each
figure.
              Fig. 14.           Fig. 15.      Fig. 16.
                     b            b           b
  The ethmoid bone derives its name from the resemblance of
its upper surface to a sieve, being full of small holes ;  it is of a
cubical form, and consists principally of numerous cells.
  a, the cribriform plate, perforated by numerous little holes*
to transmit the olfactory  nerves,  or  nerves of smelling,  into
"Foramina cribrosa, from cribrum, a sieve. 
OF  THE  HEAD.                   29
the  nostril.   In  the middle at  b,  is a  sharp  process,  the
ethmoid crest.*   From  the  lower part  descends c, the nasal
plate, making part of the central partition of the nose; d, the
flat or orbitar plates,^ which form the principal portions of the
inside of the orbits.   We see on each side of the nasal septum,
e, e, the turbinated plates, thin,  pendulous, and convex ; and
on the back  part, this bone  has numerous cells, f,f, consisting
of many convoluted  plates  of bone,  called labyrinths,  very
deserving of an attentive examination, being perhaps the most
curious bone of  the  human  body.   The  nerves of smelling,
after passing through the foramina of  the cribriform plate, are
expanded  on  the perpendicular septum, and  throughout the
whole extent of  the cells.   A very  considerable  surface is
thus provided for the distribution of the nerves, occupying little
space.
   The ethmoid  bone is joined by the  edge of its  cribriform
plate to the ethmoidal  notch of the os frontis and to the os
sphenoides; and by  the posterior part of its nasal plate to the
latter bone,  and to the vomer: by the fore part  of the same
plate to the  back part of the nasal crista of the  os frontis ; by
its anterior edge  to the os  lachrymale, and  by  the  lower edge
of the same  plate to  the superior maxillary  bone.
   There are no muscles attached to, or covering this bone.
         THE WORMIAN,  OR TRIANGULAR BONES.

             Ossa  Wormiana,  Ossa triquetra.

  These are  little irregular bones found  in  the course of the
suture formed by the parietal  and occipital bones, see Fig. 3,
d, d: their existence is not constant.
* Crista galli.                     1 Ossa plana. 
30
OSSEOUS  SYSTEM
                THE  BONES  OF THE FACE

   Are in pairs, excepting two, one  of which forms part of the
partition of the nose, and the other is the lower jaw.
   The  lines  of union  of the bones of the face have  been
called sutures, and named according to  their connexion with
each other; but the union is  rather by simple, irregular lines,
than by sutures.
              the nasal  bones.   Ossa nasi.

   Fig. 17, the external surface;  Fig.  18,    lg"   '  lg'
 the internal surface.   These bones form the
 bridge of the nose;  they are convex  exter-
 nally, thereby giving  greater resistance  to
 violence from without;  and they are concave internally for en-
 larging the cavity of the nose; * at their middle part each pre-
 sents a small foramen which passes  through  the  bone, and
 transmits a vein  to  the pituitary membrane.   Their superior
 margin is joined to the nasal process, and spine of the os frontis,
 and nasal plate of the  os ethmoides;  their  external  edges are
 received into the nasal process of the superior maxillary bone ;
 their  inner edges are  united to  each other,  and their lower
 edges are joined only by the alar cartilages of the nose.
   There are two muscles attached to them, viz. the occipito-
frontal, and compressor naris.

  * It has been stated that the inhabitants of Java, the Hottentots, and South-
 Sea islanders,  compress the  nose immediately after birth, conceiving  a
 broad nose conducive to beauty.
 
OF  THE FACE.
31
        the  lachrymal bones.   Ossa  lachrymalia.

  Fig. 19.       Fig. 19.  This  bone is nearly the  size, shape,
             tand indeed thickness of the finger  nail, therefore
         b    has  the  name also of os unguis.   It is called
             lachrymal because  a, the anterior  concave por-
tion, supports the lachrymal duct,  which conveys the  tears
from the inner corner of the eye into the nose ;  b the  orbitar
plate, which  assists in forming the orbit of the eye.
           the cheek bones.   Ossa malarum.

   Fig. 20.   The bone of the  left side.   Its several angles
      Fig. 20.       are named as  follows : a, the superior or-
                    bitar  process;  b, the  inferior  orbitar
                   process;  c, the maxillary process; d, the
                   zygomatic process.    The  concave  sur-
                    face,  e,  forms  a portion of  the orbit,
               d   called the internal orbitar process.
                      There is but one foramen,/, malar for-
amen, through which the malar nerve passes.
   The cheek bone is joined by its  zygomatic process to the
malar process of the temporal bone;  by its  superior orbitar
process to the external angle of the os frontis ;  by the posterior
edge of its orbitar plate to the os sphenoides ;  and by the inner
edge of the same plate to the os maxillare superius.
   There are four muscles attached  to it;  viz. obliquus inferior
oculi, zygomaticus major and  minor, masseter;  and the orbi-
cularis palpebrarum is extended over it.
 
32
OSSEOUS  SYSTEM
   the upper  jaw  bones.   Ossa maxillaria superiora.*

   The superior maxillary bones constitute  the principal part
 of the bones  of the  face.   Fig. 21,  the outer; Fig. 22, the
 inner view.   The body of the bone is of an irregular form,
 having a large cavi-
 ty,  a, opening into
 the  nostrils, common-
 ly called the antrum
 of Highmore.j-  On
 the outer surface is b
 the infra orbitar for-
 amen, for the  passage
 of the second  branch of the fifth pair  of nerves to the face;  c,
 the malar process ;  d, the nasal process; e, a depression contrib-
 uting to form  the small  cavity for lodging the lachrymal sack;
 this  cavity descends, and becomes at / part of the nasal duct.
 Between the  malar and nasal processes, extending backwards,
 is g, the orbitar plate.   The posterior  surface of the bone at i,
 is rounded, therefore termed tuberosity, the inner edge of which
 is rough, to join with the pterygoid process of the os palati,
 forming with  it the palato-maxillary  canal.   From the  inner
 and lower part of the body extends horizontally h, the palatine
 process, forming the  greater  portion  of the floor of the  nose,
 and hollowed below, to form an equal part of the roof  of the
 mouth.   On the upper surface is a  crest or ridge,  which  is
grooved to receive the septum of the nose.   Immediately be-
hind the  front teeth is the foramen incisivum;  the ductus in-
cisivus is a continuation of this  foramen between the palatine
 processes  into  the  nose.   There  are usually eight  alveolar
 cavities in each  bone to receive the teeth.

  * Superior maxillary bones,   t Sinus maxillaris, antrum Highmorianum.
 
OF  THE  FACE.
33
  The superior maxillary bonp is united by its malar process to
the inferior orbitar process of the os mate ; by its anterior inner
edge to the os nasi, and on the inside to the os turbinatum;  by
the upper part to the os frontis, and the os lachrymale ; by the
inner edge of its  orbitar plate to the flat plate of the os eth-
moides ;  by the posterior  point of the same plate to the os
palati.   It is connected  by its tuberosity, body, and palatine
process with the same bone ; by the inner edge of the palatine
process with that of its  fellow ; and by the nasal crest with the
vomer.
  There are ten muscles attached to this bone; viz., the con-
strictor pharyngis superior,  pterygoideus  externus, buccina-
tor, masseter, levator anguli  oris, levator and depressor labii
superioris alaque nasi, orbicularis palpebrarum, obliquus oculi
inferior, and compressor naris.
          the  palatine bones.   Ossa palatina.

   Fig,  23,  the anterior; Fig. 24,  the posterior view of the
     Fig. 23.         Fig. 24.        palate bone.  The letters
                       4?         refer to the same part in
                       k^       each figure.
                       wmS6        This bone is  placed at
                       |jJT       the lower and back part of
                       r         the  last  described bone,
below the middle region of the base of the  skull; a, the pala-
tine process, wide at its outer edge to join its fellow ; from the
outer edge of the palatine rises up b, the nasal process, which
forms a thin partition between the cell of the superior maxillary
bone and the nose; it is marked  internally by  a  strong ridge,
to which  the turbinated  bone is  attached:  behind  the nasal
process, backwards and outwards, at c, is a projecting point of
   VOL. I.               5
 
34
OSSEOUS  SYSTEM
bone, the pterygoid process; it has two grooves, one of which
terminates in /, the palato-maxillary foramen, through which
the palatine nerve and vessels proceed to the palate.  There is
another small  foramen near the last, marked g-, the palatine
foramen, to transmit branches of the same  vessels and nerves
to the soft palate.   The upper part  of  this  bone is divided by
a notch into two portions, d, the sphenoidal process, which  is
united to the body of the sphenoidal  bone, e, a  small trian-
gular portion, which, entering into the formation of the socket
of the eye, is termed the orbitar process.
   The os palati is  joined to its  fellow by the palatine process;
and  by the nasal  crest  to  the  vomer;  by the anterior  part of
the palatine process to the superior maxillary  bone;  by  the
ridge on the inside to  the  os  turbinatum;  by  the nasal and
pterygoid processes to the body and tuberosity of the os max-
illare superius ; by its pterygoid, sphenoidal, and orbitar pro-
cesses to the pterygoid process  and body of  the os sphenoides;
and by its orbitar process  to the  same process of the  os max-
illare superius, and the flat plate of  the ethmoidal  bone.
   Five muscles are attached to, and  connected with  the  os
palati;  viz., buccinator,pterygoideus externus  and internus,
constrictor pharyngis, superior, and azygos uvula.
          turbinated bones.  Ossa turbinata*

                          Fig. 25.

  Sometimes called  the inferior spongy bones, to distinguish
them from the upper spongy bones, which belong to, and are
* Ossa spongiosa inferiora. 
OF  THE  FACE.
35
a  part  of, the  ethmoidal bone.   They are pendent  in  the
nostrils,  curved,  and  exceedingly  porous  in their  texture.
    Fig. 25.       This bone is joined on the upper and on the
                  outer side to the body of the superior max-
                  illary  bone;  anteriorly to  the nasal pro-
                  cess  of the same  bone,  and   to  the  os
lachrymale;  and  posteriorly  to  the nasal  process of  the  os
palati.
                       the  vomer.

  Fig. 26, is thus named from its shape resembling a plough-
     Fig. 26.       share.   It is divided into four edges, a, the
                 sphenoidal,  the broadest, and hollowed to
                 receive the azygos process of the sphenoidal
                 bone; b,  the  anterior  or  nasal  process,
grooved to receive the nasal plate of the ethmoid bone,  and
the cartilaginous septum of the nose;  c, the inferior or crista,
uniting with the crest of the superior maxillary bone ;  d,  the
posterior or pharyngeal margin, concave and  facing  the pha-
rynx.
 
36
OSSEOUS  SYSTEM
        the  lower jaw.   Os maxillare inferius.

  This is  by far the largest bone in  the face, but it is here
divided, to show to greater advantage the outer and  inner sur-
faces.  Figs. 27, 28.  The  letters refer to each,   a, a, the
basis, is the boundary of the face ; b, b, the angle;  c, c, the

                          Fig. 27.
Fig. 28.
 
OF  THE  TRUNK.
37
 ramus;  d,  the condyle;  e, e, the coronoid process.   Fig. 28,
/, the  inferior maxillary foramen;  into which nerves and ves-
 sels enter to supply in their course through the canal the teeth,
 and afterwards to pass out at g, the mental foramen.   There
 are the same number and kind  of teeth in the lower as in the
 upper jaw, and consequently similar cavities or alveoli to receive
 them.   The number of the teeth  may be reckoned as follows,
 viz.  (on each side of the jaw,) h, two incisors, or cutting teeth;
 i, one  canine, or dog tooth; k, two small molar; I, three large
 molar, or grinding teeth.*
   The lower jaw is connected by capsular and lateral ligaments
 with the glenoid cavities of the ossa temporum, having an inter-
 articular cartilage between them.
   There are twelve pairs of muscles  attached to this  bone ;
 viz., externally, the masseteres, depressores anguli  oris, de-
 pressores et levatores labii inferioris; internally, the tempo-
 rales, pterygoid eiexterni et interni, buccinatores, mylo-hyoidei,
 genio-hyoidei, digastrici, et  genio-hyo-glossi: the platysma
 myoides passes over it.
                       CHAP. III.

               THE BONES  OF THE TRUNK.

  The trunk is composed of the spine or back bone, the thorax
or chest, and the pelvis or hips.
  The spine, though  spoken of as a single  bone,  consists of
twenty-four bones,  which turn or play upon each other, and
hence have been called vertebra.  The vertebral column sup-

  * The teeth will be particularly described at the end of the osseous system. 
38
OSSEOUS  SYSTEM
ports the trunk, head, and arms, and admits of turning and bend-
ing of the body ; indeed, it has a movement in every direction:
it forms a secure canal for conducting the delicate structure of
the spinal marrow through its whole length ;  and is remarkable
for combining those two opposite yet very essential  qualities,
strength and flexibility.
   The vertebrae are arranged in three classes, according to their
situation.   1st.  The cervical,  or those  of the neck, of which
there are seven.  2nd. The dorsal, or those of the back, which
are twelve.   3rd. The lumbar, or those of the loins, consisting
of five bones.
   As a general description  of a vertebra,  each has a body, a
large foramen to contain the spinal marrow, and several pro-
cesses.   By the junction of the processes and the bodies of  the
vertebras, the canal is formed for the spinal marrow and its mem-
branes.   The roots of those processes, called the articular pro-
cesses, are hollowed out above and below into notches ; these,
when the vertebras are fitted together, form apertures, called the
holes of conjunction, (foramina intervertebralia,) on each side
of the spine, through which  the nerves pass out from the spinal
canal.

              THE VERTEBRiE OF THE NECK.

   These are smaller than  the  other  vertebra?.   Fig. 29,  the
third, is selected as an example;
a,  the body, is longest from side
to  side ; b, the spinous process,
forked; c, c, the transverse pro-
cesses,  double, and having d, d,
circular foramina, for the pas-
sage of the vertebral artery ; e,
e,  the  superior, f, f, the infe-
rior articular or oblique pro-
Fig. 29.
 
OF THE  VERTEBRJE.
39
cesses; g, the spinal foramen, large and triangular, and, as be-
fore  stated, contributing to the formation of the canal for the
spinal marrow.
THE PECULIARITIES  OF THE VERTEBRJE OF  THE NECK.
FIRST VERTEBRA, OR ATLAS.
   The first vertebra, which, from its use in supporting the head,
has the name of atlas, consists of a ring of bone, as we observe
in Fig. 30, the upper, and Fig. 31, the lower surface.  As it
              _,.  _.               receives  the  commence-
              Fig. 30.
                                   ment of the  spinal mar-
                                   row,  the opening a,  is
                                 ^ large, and in place of  the
                                   body at the front it is fur-
                                   ther hollowed out at b, for
                                   the reception  of the den-
                                   tiform  process of the next
                                   vertebra; c, c,  the supe-
                                   rior articular processes,
                                   irregularly oval,  and con-
                                   cave ; these articulate with
                                   corresponding processes of
                                   the  skull, by which  the
                                   head has  the  power  of
bending backward and forward.   In Fig. 31, we observe e, e,
the inferior articular surfaces, are flat,  and thus  adapted  to
the superior articular surfaces of the adjoining  vertebra,  allow-
ing a horizontal motion of the head; d, d, the transverse pro-
cesses, broad, a little forked, and  perforated.
 
40
OSSEOUS  SYSTEM
             THE  SECOND VERTEBRA, OR DENTATA.*

   The most remarkable  characteristic of this vertebra is a, a
 projecting point  called                 Fig.  32.
 the tooth-like process,!
 which  rises from the
 upper part of the body,
 and has an articulating
 surface  on  its  front,
 which  is received into
 the hollow of the atlas.
 Fig. 32, b, b, the supe-
 rior articular processes
 of the dentata, are flat,
 for on these planes the atlas rotates ;  c, c, the inferior articular
 processes ; d, d, the transverse processes, small and single: the
 foramina in them are not perpendicular,  but pass upwards and
 outwards, and the spinal foramen is large.
  Thus two distinct motions are perfectly accomplished without
interfering with each  other.   When  we nod  the head, we use
the joint between the head and the first bone of the neck; when
we turn the head round,  we use the pivot joint formed by the
dentata and atlas.

    Named dentata from its projecting tooth-like process, a.
  t  Processus dentatus.
 
OF  THE  VERTEBRA.
41
THE SEVENTH VERTEBRA OF THE NECK.
Fk. 33-   The seventh vertebra is larger than the others ;  it
                              resembles in  form the third,
                              which has been  given as an
                              example and general descrip-
                              tion  of a cervical vertebra.
                              In this before us, neither a, a,
                              the transverse processes; nor
                              c, the  spinous  process, are
                              double; but the latter is  so
                              much longer than the others,
                              that this bone has  obtained
                              the name of vertebra promi-
                              nens.
              THE VERTEBRJE  OF THE BACK.

  Fio-. 34.  The twelve vertebras particularly belonging to the
back are termed dorsal.  They  are named in numerical order,
                                and diminish in size from the
                                first to the fourth, from which
                                they increase to the twelfth,
                                which is the largest:  a, the
                                 body,  is longer from front
                                 to back, than transversely; b,
                                 the superior, and c, the infe-
                                 rior articular surfaces. The
 body somewhat flattened on either  side presents small semicir-
 cular depressions, d, e,  for receiving the heads of the ribs : /,
 the superior articular process, vertical, and directed backwards;
   VOL. I.               7
 
42
OSSEOUS  SYSTEM
g, the inferior articular process, directed forwards ; h, the trans-
verse process, thicker as it extends  backwards ; i, the spinous
process, long a^d inclining downwards; j, the notch under which
pass the nerves  of the spinal cord.
              THE VERTEBRJE OF  THE  LOINS.
                         Figs. 35, 36.

   We have here two  views of a  vertebra  of the loins ;*  the
lumbar vertebrae are the
lowest five of the spine :
a, a, their bodies, though
of a circular  form  in
front, arc somewhat ob-
long from side to  side,
and larger, and of a more
spongy texture, than any
of the other classes : b,
b, b, the superior ;  c, c,
c, the inferior articular
processes,  strong  and
deep :  the superior con-
cave ;  the  inferior con-
vex ; d, d, d, the trans-
verseprocesses, are small
and  long;  these,  like
bony processes in gen-
eral, serve as levers for
the moving powers ;  e,
e, the spinous processes,
strong,  horizontal,  and
flattened at the sides ; /
the spinal  foramen. —
* Vertebra lumborum. 
OF  THE VERTEBRjE.
43
Numerous muscles are attached to the back part of the spine,
viz. the trapezii, latissimi dorsi, rhomboidei majores et minores,
levatores scapula, serrati postici superiores  et inferiores, sple-
nii, complexi, sacro-lumbales, cervicales descendentes, trachelo-
mastoidei, longissimi dorsi, transversales colli, spinales etsemi-
spinales colli, recti capitis postici majores et minores, obliqui
capitis superiores et inferiores, multifidi spina, inter spinales,
intertransversales, et levatores costarum;  on the fore part, longi
colli, recti capitis interni majores et minores, recti capitis late-
rales,  scaleni  antici, medii et postici, diaphragma, quadrati
lumborum,psoa magni etparvi, obliqui interni, et transversales
abdominis.
          GENERAL OBSERVATIONS  ON THE  SPINE.

  The twenty-four vertebras,* united by an  elastic substance,
form the spine, or vertebral column : their volume is very con-
siderable in the lumbar region, but  decreasing in  size as they
ascend to the head, though with some irregularity :  it is a pyra-
mid, reposing its base on the sacrum, as a sort of pedestal, and
having on its summit  the head.  The  spine  in front  appears
perpendicular ; a lateral view presents  a waved line, having a
very near approach to Hogarth's line of beauty.  Altogether,
the structure of the vertebral column is admirable, so that, after
an attentive examination, we are not surprised  that ail  writers
on natural theology should have selected  this  part of animal
bodies as a specimen of the most exquisite mechanism.f

  *  If we find a separate vertebra, we may know  to which  class it belongs
by the following rule, viz., the peculiar characteristic of  a cervical vertebra
is the perforations in the transverse  processes.  The dorsal are distinguished
by having articular surfaces for the heads of the ribs.  The  lumbar by their
size, and the length o'i the transverse processes.
  t  See Paxton's Paley's Nat. Theol. ch. viii.; Durham's Phys. Theol ch.
viii. 
44
OSSEOUS  SYSTEM
                     THE  RIBS, COSTJE,

   Are placed on each side of the vertebras  of the back,  and
with them form  the posterior and  lateral parts of the chest.
They are commonly divided into seven true and five false ribs,
or into sterno-vertebral and vertebral: of these, the sterno-ver-
tebral or true ribs, the seven superior, are united by means of
a portion of cartilage* directly with the sternum ; the vertebral
or false ribs, the five inferior, are either joined by their  cartila-
ges to each other, or, as  we  see  in  the two lowermost, are
totally unconnected with the sternum, and are sometimes called
loose  or floating ribs.
   The fourth rib is here taken for general  description.  Fig.
37, is the lower,  and Fig. 38, the upper edge.  It is flat within
                         Figs. 37, 38.
and without.   The vertebral extremity, a, a, is called the head,
which has an articular surface divided by  a middle ridge to ar-
ticulate with the  bodies  of the two contiguous  dorsal  verte-
bras.  The bone at b, b, is contracted, forming the neck; at the
back  of the rib is c,  c, the  tubercle, having  a  plain articular
* Gristle. 
OF  THE  RIBS.
45
surface  for the transverse process  of the vertebra;  further out-
ward the  bone suddenly bends  forward, producing d, d,  the
angle, from which proceeds  the body, which in its natural sit-
uation passes  forwards and  downwards to e,  e, the sternal ex-
tremity, where it has a slight oval concavity to which  the car-
tilage adheres, and which cartilage joins the rib to  the  sternum
or breast bone.   At the under edge of each rib we find, Fig.
 37,/ a groove for the intercostal  vessels  and nerves.
   From the  first  to the seventh pair,  the ribs  increase  in
length ; this gives the chest its conical shape : from the seventh
they begin  to  decrease  in  length to  the twelfth, which is as
short as the first: and with regard to  the direction of  their in-
clination, that of the first is nearly horizontal, whilst the lower
ones dip down more  and more at their points.   But there are
other remarkable distinctions in the first,  eleventh,  and twelfth
ribs — as
                   THE FIRST RIB.


Fig. 39.   The first rib is  very short,  and much curved.
                                 It is flat above and be-
                                 low ; a, the head; b, the
                                 tubercle, large and placed
                                 at the angle of the bone;
                                 c, the sternal extremity,
                               b which  is  united to the
                                 breast  bone  by a  short
                                 portion  of cartilage  at a
                                 right angle.
 
46
OSSEOUS  SYSTEM
           THE ELEVENTH AND TV ELFTH RIBS.


  Fig. 40,  is  the twelfth rib;  the eleventh is  like  it, only
a little longer.    They do  not             Fig. 40i
articulate with  the transverse
processes of the vertebras, and
are  unconnected   with   the
breast  bone.   These  ribs  are
much shorter than  all the others, except the first;  their heads
have only single articular surfaces to join with the whole artic-
ular cavities of the two lowest dorsal vertebras.
   The muscles attached  to the  ribs are ;  the pectorales majo-
res et minores, subclavii, sterno-thyroidci, scaleni antici, medii,
et postici, latissimi dorsi, serrati majores  antici,  superiores et
inferiores postici, sacro-lumbales,  accessorei ad  sacro-lumba-
les, longissimi dorsi, levatores et depressores costarum, inter-
costales, sterno-costalis, diaphragma, obliqui  externi et interni,
transversales, et  recti abdominis, et quadrati lumborum.
               THE BREAST  BONE,  STERNUM.


  The situation of the sternum, or breast bone, is well known.
It is connected with  the  cartilages  of the ribs, and  with the
collar bones, and  is usually  divided  into  two  or  three parts.
In the position before us, Fig. 41, it consists of two bones.
 
OF THE  STERNUM.
47
                       The first is broad  and thick above, and
                       a little contracting as it descends.*   It
                       is irregularly  convex before, and con-
                       cave behind.   At the upper angle,  a,
                       the  collar bone,  is articulated ;  b, the
                       articular surface for the cartilage of the
                       first rib ;  c, the depression,  which, with
                       the depression of  the  second bone, form
                       an articular surface for the cartilage of
                       the  second rib:  d, e, f, g,  mark  the
                       concave articular  surfaces of the third,
                       fourth,  fifth,  sixth, and  seventh ribs ;
                      g, points  to the two last depressions of
                       articulation, which are contiguous.
                        There  are  transverse  lines on  the
                       lower bone,  which indicate its further
                       division in early life.
                        h, The ensiform or  xiphoid cartilage,
terminates the lower extremity of the sternum.   In the adult
it is frequently ossified.
  The sternum, ribs,  and  dorsal vertebras, form  the chest or
thorax, the offices and  uses of which  are multiplied; for it is
the centre of motion  for  directing the animated machine, pro-
tects  the  heart,  lungs, and  other  important parts;  but  its
agency in respiration  must  be considered its most important
function.   The muscles attached to the sternum are the pecto-
rales  majores,  sterno-cleido-mastoidei, stemo-hyodei, sterno-
thyroidei, et intercostales interni.
* This portion of the sternum is called the manubrium or the handle. 
48
OSSEOUS  SYSTEM
               THE  BONES  OF THE PELVIS.

  The large bony cavity situated  at  the lowest part  of  the
trunk, by which its weight is  transferred to the lower extremi-
ties, is called the basin or pelvis;  for  it in part contains and
supports  the bowels and  other viscera.  It consists of a pair,
and two or more single bones.
           unnamed  bones.   Ossa innominata.

  The two large,  broad, and  irregularly shaped bones, called
ossa innominata or hip bones, constitute the fore part and sides
of the basin, and the lower part of the sides of the abdomen —
the upper edge is frequently called the hip.
  Each bone is usually described as three bones, from its hav-
ing been composed of three distinct pieces in the first period of
life:  these  portions retain the same name though  united in
one solid broad bone.  To obtain therefore a knowledge of the
    Fig. 42.       terms employed  in this description, we must
                 advert to its original construction.   Fig. 42
                 shews the three portions united by cartilage ;
                 a, the  ilium;  b,  the ischium;  c,  the  os
                 pubis ;  the  subsequent description will have
                 a reference to these terms.
 
OF THE  PELVIS.
49
Fig. 43.
VOL.  I. 
50
OSSEOUS  SYSTEM
   Fig. 43, the outer surface of the hip bone, or os innominatum;
Fig. 44, the inner surface.  The letters refer to both views ;  a,
the dorsum  or back of the ilium ; b, the  crest; c, the anterior
superior spinous process ; d, the anterior inferior spinous pro-
cess; e, e, the posterior superior and inferior spinous  proces-
ses ; f  the fifth spinous process,  but  is  distinguished  by the
term ischium; g,  the greater  ischiatic  notch.   The  inner
surface, h, of the os innominatum, or rather that portion  of it
called the ilium, is concave  and  smooth ;  i, an elevated line,
the linea innominata or linea ilio-pectinata, which, when join-
ed to its fellow, forms part of the brim of the pelvis ; j, a large
uneven  articular surface  for the sacrum ; k, a large and  deep
hollow, the  socket for the head of the  thigh bone, called the
acetabulum, from its resemblance to a measuring cup used by
the ancients.  The margin is not perfectly circular, but appears
deficient at the under part, forming a notch, which in the recent
subject  is filled up with ligament to complete the  edge of the
cup.  In the  centre of this cavity, and continued to the notch is
a depression, to which the round ligament of the thigh bone  is
fixed ; I, the lesser ischiatic notch; m, n, the tuberosity of the
ischium ; o, the ramus of the ischium ; p, the pubis;  q,  the ob-
turator  or thyroid foramen.   The muscles attached  to and
covering the os innominatum, are the psoas magnus et parvus,
iliacus,  levator ani,  obturator in/ernus, pyriformis, coccygeus,
obliquus externus et internus,  transversalis, rectus, et pyrami-
dalis abdominis, quadratus lumborum, longissimus dorsi, sacro-
lumbalis, et latissimus dorsi, tensor vagina femoris, sartorius,
gluteus  maximus, medius et minimus, rectus femoris, gemini,
quadratus femoris, biceps flexor cruris, semitendinosus et semi-
membranosus, transversus perinai et transversus perinai alter,
ischiocavernosus, triceps adductor femoris,  gracilis, pectineus,
et obturator externus. 
OF THE  PELVIS.                  51
OS  sacrum.
Fig. 45.
   Fig. 45.   The sacrum is the basis which supports the ver-
                                   tebral column. The sacrum
                                   is placed between  the ossa
                                   innominata,   to  form  the
                                   posterior part of the cavity
                                   of the pelvis.   On the front
                                   and concave surfaces  are
                                   four  lines,  indicating  the
                                  junction of the different pie-
                                  ces of which it is composed
                                   during infancy,*   Here we
                                  have a posterior view of the
                                   adult bone; a, the part with
                                  which the body of  the last
                                  vertebra of the loins artic-
                                  ulates ;  b,  b, the articular
                                  processes, which correspond
                ^8                with  the inferior articular
                                  processes of the lowest,Ver-
tebra of the loins ; c, c, the uppermost of eight foramina, called
the posterior sacral foramina, for the passage of small  nerves
and vessels.  Between these are four eminences,  short and hor-
izontal, forming a continuation of the line of the  spinous pro-
cesses of the  vertebras.   Above is  the commencement of the
sacral canal,  terminating below at g; this  canal receives the
extremity of the spinal marrow, which in this  situation  is ex-
ceedingly fibrous, and, from the nearly parallel disposition of the
nerves  that issue from it, has obtained the name oicauda equi-
na, or  horse's  tail; d,  d, the  lateral surfaces,  irregular and
"These have been called the false vertebrae. 
52
OSSEOUS  SYSTEM
rough, articulating with the hip bones ;  e, an oval surface unit-
ing with the os coccygis.  The muscles attached to the sacrum
are the longissimi dorsi, sacro-lumbales, multifidi spina, glutei
maximi, pyriformes, et coccygei.

                the coccyx.  Os coccygis*

   The os coccygis, f, Fig. 45, is  divided  into several  bones
which are appended to the sacrum ; and although in advanced
age it is one solid bone, yet in the prime of life, as is represented
in the present instance, it  consists of four distinct bones.   The
upper one is united  to the sacrum by a flat surface, on each side
of which are  projections called the cornua.  The only muscles
attached to this bone are the coccygei.
                        CHAP. IV.

            BONES OF THE  UPPER EXTREMITY.

  The upper extremity consists of the collar bone, the shoulder
blade, the arm, the fore arm, and the hand.

               THE  COLLAR BONE,  Clavicula,

  Termed clavicle from its resemblance to an ancient key, has
a body and  two  extremities.   Fig. 46,  a,  the sternal ex-
                          Fig. 46.
* So called from its figure being somewhat like a cuckoo's beak. 
OF THE  UPPER EXTREMITY.           53
tremity, presenting a triangular surface for its articulation, by
means of an  intervening  cartilage, to the  sternum ;   b,  the
rhomboid process; c, the tubercle;  d,  the scapular extremity,
which is the flattest part of the bone, and has a narrow articu-
lar surface for the acromion of the scapula.
  The muscles attached to the clavicle  are six ;  to its under
part, the pectoralis major,  deltoides, and subclavius ; and to its
upper part, the trapezius, sterno-cleido-mastoideus, and sterno-
hyoideus.
  The clavicle tends to prevent the arm from falling forward
on the breast; and  increases the sphere of action  of the arm,
by enabling it to  describe a circle, the centre of which is  the
connexion of the clavicle with the shoulder.
             THE  SHOULDER BLADE.   Scapula.

  The scapula or shoulder blade is situated on  the back and
upper  part of  the ribs, and forms the posterior  part of the
shoulder.  Its form  is  an irregular triangle; it  is flat, and so
very thin as  to be transparent in  its  greatest extent.   This
bone is retained in its situation merely by muscles that unite  it
to the head,  the os hyoides,  the ribs, the  vertebras, and the
upper arm bone ;  by means  of these muscles it  consequently
has the power of moving upwards, downwards, backwards, and
forwards ; and by a quick succession of these  motions the arm
is rotated.  Thus  the scapula serves not only as a support, but
a fulcrum for every action of the superior extremity.
  Fig. 47, the front; Fig. 48, the back view. 
54
OSSEOUS SYSTEM
m
Fig. 48.
a    h
  The scapula is usually described with  reference  to its trian-
gular figure ; a, a, the superior angle; b, b, the inferior angle;
i 
OF THE  UPPER EXTREMITY.           55
 c, the outer angle, having an oval concave articular surface ; d,
 d, the glenoid cavity, or socket  in which the head of the arm
 bone is articulated ; around which the bone becomes contracted,
 at e, e, forming the neck.   The sides of the triangle are thus de-
 nominated ; /, /, the basis ; g, g, the inferior border, or casta;
 h,h, the superior border; i,  the fossa for  the  attachment of
 the infra-spinatus  muscle;  k,  the fossa for the  attachment  of
 the supra-spinatus muscle ;  I, I, the commencement and course
 of the spine,  terminating in a flat projection; m, m, the acro-
 mion* which  we see extended  over the  glenoid cavity, pro-
 tecting the  joint,  and forming the  point of  the shoulder  to
 which the collar bone is  articulated.  There is another projec-
 tion, n, n, compared to the beak  of a crow, therefore  termed
 the coracoid process ;  this also guards the shoulder  joint, and
 with the acromion gives advantageous points of attachment  to
 muscles which move the  arm.   Between the coracoid process
 and the superior border  is o,  o, an  indentation,  the semilunar
 notch, which  is formed into a  foramen by a  ligament, and
 affords a passage for the supra-scapular artery, vein, and nerve.
   The muscles attached  to this bone are  sixteen in  number;
 viz., to  the spine above, the  trapezius, and below, the del-
 toides ;  to the base, the  levator scapula,  rhomboideus minor
 et major, and  serratus magnus; to  the notch in the superior
 border, the omo-hyoideus; to the fossae, the supra-spinatus, in-
 fra-spinatus,  and subscapularis; to the inferior border,  the
 teres minor, and the long head of the triceps extensor cubiti ;
 to the inferior  angle, the teres major; and to the  coracoid pro-
 cess, the  coraco-brachialis,  pectoralis minor,  and the  short
 head  of the  biceps flexor cubiti, the long  head of which mus-
cle has an attachment to the glenoid cavity.
* The point of the shoulder. 
56
OSSEOUS  SYSTEM
the upper arm.  Os brachii.
  The upper arm consists of a single bone, called also os hu-
meri.  Fig. 49 represents  the back, Fig. 50 the front view ;
a, a, the head, is hem-        Fig. 49.         Fig. 50.
ispherical, standing ob-
liquely backwards from
the  bone,  and  when
received into  the gle-
noid cavity of the scap-
ula  constitutes  a ball
and socket  joint;  b,
the  smaller  tubercle;
c, the greater tubercle;
they are separated by
e, a channel* in which
the tendon of the long
head of the biceps mus-
cle plays.  The bone is
contracted at d, d, and
forms  the  neck.   The
body  of the bone is
nearly  cylindrical. —
The  lower  extremity
of the bone is flatten-
ed, and constitutes with
the ulna a perfect hinge
joint; /,  the outer condyle; g, g, the  inner condyle, more
projecting than the outer, as it gives attachment to the flexor
muscles of the fingers.  The lowest  part  of the bone  has
two articular surfaces :  that on the outside,  h, convex, for the
head of the radius;  that on the inside,  i, concave from side to
The bicipital groove. 
               OF  THE  UPPER  EXTREMITY.            57

side, but convex from back to front for the reception of the sig-
moid cavity of the ulna.  Above the articulation, and in front,
Fig. 49, there  is a depression for the coronoid process  of the
ulna.  Behind, Fig. 50, is another depression for the olecranon
of the  ulna ; j, the foramen for  the  medullary artery,  which
supplies the circulation  of blood to the marrow of the bone.
   There are twenty-four muscles  attached to the  os  humeri;
viz., the deltoides, supra-spinatus, infraspinatus, teres minor,
subscapularis, pectoralis  major,  latissimus dorsi,  teres major,
coraco-brachialis, triceps  extensor cubiti, brachialis internus,
palmaris  longus, flexor  carpi radialis, flexor carpi ulnaris,
flexor  digitorum  sublimis, flexor longus  pollicis,  pronator
radii teres, supinator  radii longus  et  brevis, extensor carpi
radialis  longior et  brevior, extensor carpi  ulnaris,  extensor
digitorum communis, and anconeus.
                   THE  FORE  ARM

Consists of two bones, the ulna and radius.
VOL. I.
9 
58                 OSSEOUS SYSTEM
     THE ULNA OR LARGER BONE  OF THE  FORE ARM.

                           Fig. 51.

   The ulna is placed on the inside of the fore arm by the side
of the radius.  The upper extremity  is large  and  scooped  out
in front,  a, forming the greater sigmoid cav-       FlS- 51-
ity ; this is the cavity which articulates with
the base of the os humeri.  Below, this ap-
parent excavation is bounded by 6, the coro-
noid process, above, by e, the  olecranon,  or
elbow ; this point serves  as a lever  for the
extensors of the fore arm.   There is a small-
er concave articular surface for the head  of
the radius at c, the lesser sigmoid cavity;  d,
a small eminence, called the tubercle.  The
body or shaft of this bone is strongly marked
by muscles, and by the ligament interposed
between the bones.  The lower  end has a
rounded articular surface, f for the radius,
and beneath,  a  shallow cavity for an inter-
articular cartilage, the medium  of connexion
with the wrist.   On the inside, its lengthened
point, g, forms the styloid process.
   There are fourteen muscles attached to the
ulna;  viz., the  brachialis internus,  triceps
extensor cubiti, anconeus, pronator radii teres, flexor carpi ra-
dialis, flexor carpi ulnaris, flexor digitorum sublimis et profun-
dus, pronator quadratus,  extensor carpi ulnaris, extensor ossis
metacarpi pollicis, extensor primi internodii pollicis, and in-
dicator.
 
OF  THE  UPPER  EXTREMITY.
59
THE RADIUS.
a—i
   The radius, or smaller bone of the arm, is supposed to be so
    Fig. 52.       named from its imaginary resemblance to the
                 spoke of a wheel, or to  a  measure  used by
                 the ancients.  It is placed on the outside of
                 the fore arm ;  a, the  body of the  bone, in-
                 clines to a triangular form ;  b, the upper ex-
                 tremity, or head, presents a  circular cavity,
                 articulating with  the smaller condyle of the
                 humerus ; its  circumference joins with,  and
                 turns into the  smaller sigmoid cavity of the
                 ulna; below,  at c,  the  bone is contracted,
                 forming a neck,  which terminates  in d,  the
                 bicipital tubercle, to which is fixed the biceps
                 muscle.  The lower end has e, a superficial
                 cavity,  articulating with the  scaphoid  and
                 semilunar bones  of the wrist.  On  the inner
                 side there is a narrow concavity, in which the
                 lower extremity of the ulna rotates.   The ex-
                 treme point, /, is termed the styloid process.
   There are eight muscles attachedjto the radius ;  viz. the su-
pinator radii longus et brevis, pronator teres et quadratus, bi-
ceps flexor cubiti, flexor digitorum  sublimis, flexor  longus,
extensor ossis metacarpi pollicis.
   Paley has not passed unobserved the remarkable  mechani-
cal contrivance of the fore arm.  For the perfect use of the fore
arm two motions are wanted ;  a motion at  the elbow backward
and forward, which is called a reciprocal motion; and a rota-
A
f
I 
60
OSSEOUS SYSTEM
 tory motion, by which the palm of the hand  as  occasion  re-
 quires, may be turned upward.   How  is this managed ?  The
 fore arm consists of two bones lying along side  each other, but
 touching only near the ends.   One, and only one, of these bones
 is joined to the humerus at the elbow ;  the  other alone to the
 wrist.   The first, at the elbow, by means of a hinge joint, which
 allows of motion in the same plane, swings  backward  and for-
 ward, carrying along with it the other bone, and the whole fore
 arm.   In the mean time, as  often as there  is occasion to turn
 the palm upward, the bone, to which the hand  is attached, rolls
 upon the first, by help of a groove or hollow near the end of
 one bone, to which is fitted a corresponding prominence in the
 other.
  The first is at liberty at one end, the second at the  other; by
 which means two actions  may be performed together.  The os
brachii may be swinging with its hinge joint at the elbow, at the
very time that the radius which  carries the hand, may be turn-
ing  round in its groove.
                       THE HAND.

  The last division of the superior extremity is the hand ; it in-
cludes the wrist, the palm of the hand, and the fingers.
           THE  BONES  OF THE WRIST.   CarpUS.

   The wrist or carpus consists of  eight  small  bones dis-
posed in two  rows, forming an arch supported by ligaments.
Fig. 53 is  the back of the wrist,  (as the shape  of the sev- 
OF  THE  UPPER  EXTREMITY.          61
                                  eral  bones is best seen in
                                  this direction);  a, the boat-
                                  shaped or  scaphoid  bone;
                                  b,  the half-moon or semi-
                                  lunar bone ; c, the wedge-
                                  like or cuneiform bone ; d,
                                  the pisiform bone, fro m  its
        / d  ^     \            size  and figure resembling
        h     K    f               i            11.
                    J             a  large pea.   In the sec-
 ond range we  observe  on  the  outside,  e, the  trapezium;
f, the trapezoid bone ;  these last  two are named from their
 figure; g, the  large  bone, os  magnum; h,  the unciform
 bone, named from its hook-like process, which  projects into the
 hand.   From the figure before us we may form a tolerably
 correct idea  of  their union and  arrangement: on the back of
 the hand the wrist bones  are convex, in front  concave, the
 arch giving  additional strength, while the projecting pisiform
 bone and unciform process  increase the concavity for the  pass-
 age of the flexor tendons of the fingers.
   The bones of the carpus  have a gentle motion on each other,
 and on the fingers; they  also admit  of  a limited motion  in
 every direction with the bones of the arm.
   There are two muscles  attached to the os  pisiforme; viz.,
 the flexor carpi  ulnaris, and abductor minimi digiti:  to the
 trapezium four;  viz., the flexor  ossis  metacarpi pollicis, ab-
 ductor pollicis, abductor indicis, and extensor ossis metacarpi
pollicis.  The only muscle attached to the trapezoid bone is
 the flexor brevis pollicis.   To the  os magnum also the  same
muscle is attached.   The muscles inserted into  the unciform
bone are three;  viz.,  the flexor brevis pollicis,flexor proprius
pollicis, and abductor minimi digiti. 
62
OSSEOUS  SYSTEM
THE BONES  OF THE PALM  OF THE  HAND.
Metacarpus.
  The bones  called the metacarpus, Fig. 54, form the palm
and  back  of  the  hand; they sustain  the fingers.   We ob-
            Fig. 54.            serve  each  bone  long  and
                              rounded, the  ends larger than
                              the bodies.   Their upper ends
                              have plane surfaces  to  unite
                              with the  carpus; and  where
                              the metacarpal bones  are con-
                              tiguous  to each  other, they
                              have also  flat  articular  sur-
                              faces ;  their lower ends artic-
                              ulate with the fingers by con-
vex heads, to  allow of  a free motion  in every  direction;  we
have at this  joint a  lateral motion, as well as  flexion  and
extension.*
  There are eleven muscles attached to the metacarpal bones,
viz., seven interossei, common to all; to that of the fore finger,
the flexor  carpi radialis and  extensor carpi radialis longior;
to that of the middle finger, the extensor carpi radialis brevior;
and to that of the little finger, the extensor carpi ulnaris.
  * Those anatomists who  reckon five metacarpal bones include the first
bone of the thumb. 
OF  THE  UPPER  EXTREMITY.           63
the bones  of the fingers.   Phalanges digitorum.
b  -
            Fig. 55.
                                   Fig. 55.   The  fingers
                                 consist of  twelve  bones,
                                 arranged  in  three  rows,
                                 termed phalanges.   They
                                 are  rounded on  the  back,
                                 as  we see in  this figure,
                                 but flat and somewhat con-
                                 cave  in front, as  may  be
                                 observed in  Fig. 56.
                                   The first  phalanx  or
                                 row, a, a, has  sockets  at
                                 the superior extremities  to
                                 articulate with   the  meta-
                                 carpal bones ; the inferior
extremity is  convex  from back  to front, concave from side
to side.
   The second phalanx, b, b, has  on the  upper ends concave
articular surfaces, with a little rising in the middle, dividing them
into two smaller concavities, adapted to  the lower  extremities
of the first phalanx.    The lower ends of the second phalanx
are similar to the lower ends of the first.
   The  third phalanx, c, c, has a joint similar to the second ;
the points are rough in front, but rounded at  the backs  to re-
ceive the nails.
   There are eighteen  muscles  attached  to the  phalanges, or
finger bones ; viz., in  front, the flexor digitorum  sublimis et
profundus; flexor longus et brevis, adductor, et abductor indi- 
64
OSSEOUS  SYSTEM
cis; flexor proprius, et abductor minimi digiti ; four lumbri-
cales and seven interossei.  At the back the extensor digito-
rum communis and indicator.
the bones  of the thumb.
Fig. 56.
   The bones of the thumb, Fig. 56, a, b, c,
very much resemble the bones of the fingers;
but as  the thumb is the  antagonist of the
fingers,  it  is  much thicker  and  stronger.
The first bone  is  connected by a double
articular surface to the trapezium.
   The muscles attached to the front of the
thumb, are the flexor brevis  et flexor ossis
metacarpi pollicis, and  abductor indicis; to
the back  of the thumb the extensor primi
internodii pollicis.
 
OF  THE  LOWER EXTREMITY.           65
Fig. 57, a front view of the bones of the hand.

                        Fig. 57.
                        CHAP. V.

         the  bones  of the lower  extremity.

  The lower extremity consists of the thigh, leg, and foot.


             THE THIGH BONE.  Os femoris.

  The thigh has one bone ; it is the longest of the human skel-
eton, and is remarkable for its strength,  supporting  the  whole
trunk and upper extremities, and often with the addition of bur-
dens greater than the weight of the body itself.   This bone is
placed obliquely,* from the great breadth  of the pelvis; and
VOL. I.
  *  See Tab. i, ii,
10 
66
OSSEOUS  SYSTEM
this obliquity of the  shaft of the  bone is  necessary  to bring
it more immediately under the centre of gravity, and to  render
our steps not only more direct, but more quick and secure.*
Fig. 58.                     Fig. 59.
a      c                          a
  * " Whilst a man stands on both his legs, the thigh bones are oblique to
the gravitation of the body; but when one foot is raised, the whole  body
being then balanced on one foot, a change takes place in the position of the
thigh bone, and the obliquity of that bone is diminished; or in  other words,
now that it has the whole weight to sustain, it is perpendicular under it, and
has therefore acquired great strength." — Animal Mechanics. 
OF  THE  LOWER  EXTREMITY.           67
  Fig. 58 is the front, and Fig. 59 the back of the  femur or
thigh bone ; a, a, the head of the bone,  forming the  greater
portion of the sphere ;  it articulates with  the hip, and  is the
most complete instance of the ball and socket joint that we can
produce.   Besides a surrounding ligament, common to all joints,
it has an additional security in a short, strong, yet flexible liga-
ment, inserted by one end into the ball, at  the depression, b, b,
by the other end into a cup, or acetabulum of the hip bone ;  c,
c, the neck;  d, d, a large process, called the trochanter major;
e, e, a smaller projection, the  trochanter minor.   The curved
line  at/, Fig. 59,  the linea quadrata, extending from one  tro-
chanter to the other, shows the attachment of the capsular lig-
ament, and the quadratus femoris ; g, g, the body of the bone ;
h, h, a long,  rough, elevated  line, the  linea aspera ; i, i, the
outer, and k, k, the inner condyle; these have  four articular
surfaces ; /, m, the two upper on the fore  part,  for the patella
or kneepan ; n, o, the two lower, for the large bone of the leg.
The latter articular surfaces are separated by p, a  deep  recess,
into which the cross ligaments are inserted ;  it also affords pro-
tection to the large vessels and nerves passing to the leg.  The
medullary artery enters at q, about the  middle of the bone.
   There are nineteen muscles attached to this bone, viz. the
gluteus medius et  minimus to the trochanter major; the psoas
magnus and iliacus internus to the trochanter minor ;  the quad-
ratus to the linea quadrata ; the obturator  internus et externus,
gemini, and pyriformis, to the fossa trochanterica ; the gluteus
maximus, pectineus, and triceps femoris, vasti,and biceps flexor
cruris, to the linea aspera ;  the gastrocnemii,  plantaris, and
popliteus, to the condyles ; the cruraus, sartorius, gracilis and
tensor vagina femoris, are situated on the fore part of the femur,
but are not adherent to it. 
68
OSSEOUS  SYSTEM
                 the knee pan.   Patella.

  The small round bone at the knee is called patella ; it is sit-
uated at the  front of the         Fig. 60.           Fig. 61.
knee joint.   Fig. 60, the
anterior surface, convex
and rough from the adhe-
sion of the fibres of a ten-
don which is spread over it.   Fig.  61, the posterior surface,
which  indeed is  divided by  a  perpendicular  ridge into  two
slightly concave articular surfaces.  This bone  gives  to the
tendons which bring forward the leg a very considerable  me-
chanical advantage, by altering the line of their direction,  and
by advancing it further out from the centre of motion,  and this
upon the principles of the resolution of forces, upon which prin-
ciples all machinery is founded.
 
OF THE  LOWER  EXTREMITY.           69
THE SHIN bone.   Tibia.
   The tibia is the large bone of the leg, situated at the inner
 side;  Fig.  62,  the  front;  Fig. 63,  the  side view,   a, the
                                  head, having  two semicir-
                                  cular articular concavities,
                                  b, b, b,  for the condyles of
                                  the  thigh bone; these con-
                                  cavities  are separated by c,
                                  c, a middle  ridge or spine,
                                  to which the cross ligaments
                                  of the knee are secured ;  d,
                                  d, the tubercle which gives
                                  attachment to  the ligament
                                  of the patella ; e, e, a small
                                  articular surface for the head
                                  of the fibula or small bone
                                  of the leg; //,  the spine
                                  or shin ; g, the outer side
                                 of the  base, having i, a de-
                                  pression, or articular surface
                                 for the lower  extremity of
                                 the fibula; h, the  inner an-
                                 kle,  called  the inner mal-
                                 leolus, on  the under and
back part of which is  a groove, for the passage of the tendon of
the tibialis posticus muscle ; k, k, the surface for connecting it
with the astragalus, or bone of the foot; /, the foramen for the
medullary artery.
  There are ten muscles attached to the tibia, viz. the sarto-
rius, gracilis, and semitendinosus, immediately below the tu-
 
70
OSSEOUS  SYSTEM
bercle ; the semimembranosus, to the back part of the head of
this bone ;  the popliteus, soleus, tibialis posticus,  and flexor
longus digitorum pedis, to the back part of its head and body ;
the tibialis anticus and  extensor longus digitorum pedis, are
situated on the fore part of its head and body.
THE SPLINT BONE.
Fibula.
   Fig. 64.   The small bone of the leg  is called fibula, from
its resemblance to the pin of a brooch ; it is placed on the out-
side of the leg ;  the  shape of the bone is          Fig. 64.
irregularly triangular ;  a, the head or up-             b
per extremity : it has a smooth  articular
surface at b, on its inner side, to join with
the tibia.    The body  presents several
ridges  and  depressions for the lodgment
and attachment of muscles ; c, the infe-
rior extremity,  lengthened  to  form  the
outer ankle, or external malleolus;  d, an
oblique articular surface,  for  the outside
of the astragalus.
   The ankle joint is strengthened and de-
fended from  injuries by those  remarkable
prolongations of the tibia and fibula which
we name the external and internal mal-
leoli, the outer and  inner  ankle.  If the
joint is in danger of dislocation outward, it
is curbed by the inner projection, i. e. that
of the tibia ; if inward, by the outer pro-         ,
jection,  i. e. that of the  fibula ; between
both it is locked in its  position.
   Eight muscles are inserted into this bone, viz. to the upper
extremity the biceps flexor cruris;  to the fore part of its body, 
OF THE  LOWER  EXTREMITY.           71
the extensor longus digitorum and  extensor proprius pollicis
pedis; on the outside the peroneus  longus  et  brevis; and be-
hind, the  soleus, the tibialis posticus, and flexor longus pollicis
pedis
THE BONES OF  THE FOOT.


          Fig. 65.
  Fig. 65 is a general view of the skeleton of the  foot, which
consists of twenty-six bones ; d, e,f g, h, and two intervening
bones, called the tarsus or instep ; a, the metatarsus or middle
row of bones of the foot; and b, c, i, the three phalanges of the
toes.  The bones of the foot somewhat resemble the hand, but
they are stronger, larger, and less calculated for motion.
                 BONES  OF THE TARSUS.

  The tarsus or instep consists of seven bones, and when joined
they form ao arch, under which tendons, vessels, and nerves pass
into the sole of the  foot. 
72
OSSEOUS  SYSTEM
Fig. 66.
                     THE  ASTRAGALUS.

   1st.    The astragalus,  so
called from its resemblance  to
an  ancient  die ; or rather, 1
am inclined to think, because
a game of dice was played with
the talus or huckle bone of an-
imals  to which  this  corres-
ponds,   a, a large articular
surface:  above,  it is convex
from front to back, forming  its
largest articular surface for  the base of the tibia ; b, the articu-
lar surface for the lower extremity of the fibula : on the oppo-
site side  is a surface for articulating with  the inner malleolus ;
the fore part of the bone, c, is  rounded  to articulate with the
scaphoid bone ;  the under part, d, rests  on the heel  bone by
two articular surfaces, separated by a deep groove.
   The only muscle attached  to this bone is the tibialis posti-
cus.
THE HEEL  BONE.   Os Calds.
   2d.   The os calcis is
the largest bone  of  the
foot;  a, the tuberosity or
heel; on the fore part are
two articular surfaces, at
b, c, for the astragalus ;  d,
an  articular  surface for     c
the cuboid bone.
   There are eleven muscles  attached to the os  calcis,  viz. to
 
              OF THE  LOWER EXTREMITY.           73

the upper part, the extensor brevis  digitorum pedis;  to  the
under part, the adductor, flexor brevis, abductor pollicis pedis,
flexor brevis digitorum, flexor digitorum  accessorius, and  ab-
ductor minimi  digiti pedis; posteriorly, the gastrocnemii, so-
leus, and plantaris.



             the  scaphoid, or navicular bone.

   3d.   The os scaphoides, or boat-shaped bone, is  placed on
the inner part of the foot, before  the astragalus ; at b it is con-
                  Fig. 68.            Fig. 69.
cave to articulate with that bone ; in front at a, its general as-
pect is convex, but its convexity is divided into three flat artic-
ular surfaces, for the three cuneiform  bones.  See  Fio-. 69,
a, b, c.
   The tibialis posticus muscle is attached to this bone.
                 THE  CUNEIFORM  BONES.

  The cuneiform or wedge-like bones are three in number, de-
nominated from their position the inner,  the  middle and the
outer cuneiform  bones.   They are applied to each other like
the stones of an arch.
VOL. I.
11 
74
OSSEOUS  SYSTEM
               THE INNER CUNEIFORM BONE.

   4th.   This bone is the largest of the three ; it has four artic-
ular surfaces : one behind,  to  form part of  the articulation for
the scaphoid bone ; another before, with a plain articular sur-
face for the metatarsal bone of the great toe:  its outer surface,
                 i. e. the side towards the centre of the foot, has
                 a flat articular surface for  the middle wedge-
                 like bone, and a smaller surface for the meta-
                 tarsal bone of the second toe ; posteriorly, the
                 three cuneiform bones form a cup,  into which
                 is received the rounded articular surface of the
scaphoid bone ; anteriorly, they join with the three large rneta-
tarsal bones, and, in consequence of the shortness of the middle
cuneiform bone, they  are locked together like a  mortice and
tenon.  The middle bone articulates  on the inside with the in-
ner, and on the outside with the outer cuneiform bones ; and the
outer cuneiform is connected by its outer surface with the cuboid
bone.
   There are five muscles attached to these bones,  viz. to the
inner, the tibialis anticus and peroneus longus ; to the outer,
the flexor brevis and abductor pollicis pedis;  and  the tibialis
posticus to all three bones.
              THE MIDDLE CUNEIFORM BONE.

  5th.   This is the smallest of the  cuneiform
four articular surfaces ;  one behind  for the
scaphoid bone, one before for  the  metatarsal
bone of the second toe, and one on each side
for the first and  third cuneiform bones.
bones;  it has
    Fig. 71.
 
OF THE  LOWER  EXTREMITY.           75
THE OUTER  CUNEIFORM BONE.
6th.  This bone has  five articular  surfaces ; one behind for
 Fig. 72.        the scaphoid, one before for the third meta-
               tarsal bone, two for the  inside, i. e. for the
               middle cuneiform and second metatarsal, and
               one  on  the  outer  surface for the cuboid
               bone.
the cuboid bone.  Os cuboides.
  8th.   Though this bone is so named from  its shape, it is  a
         Fis 73               very irregular cube : it has three
                              articular surfaces, a, the largest
                              of which, is  posterior, and con-
                    ... a       nected to the os calcis ; b, the
                              anterior, for the fourth metatarsal
                              bone ;  the smallest  is  articula-
ted on the inner surface to the scaphoid and  outer  cuneiform
bones.  This bone is convex on its upper surface, and on the
lower surface it has a deep groove, in which the tendon of the
peroneus longus muscle plays.
  There are two muscles attached to the os cuboides, viz. the
flexor brevis minimi digiti, and adductor pollicis pedis.
 
76
OSSEOUS  SYSTEM
the metatarsal  bones.
  a, The metatarsus consists of five bones.  Fig.  74, a, the
first, or that of the great
toe,  is  the  largest  and
Fig. 74.
Fig. 75.
thickest;  the other meta-
tarsal bones are long and
slender.   Fig. 75, a the
second, is the longest; the
others decrease in length to
the fifth or little toe.  Each
bone has flat articular sur-
faces to  unite  with the
tarsus, and a rounded  ar-
ticular surface for the first
bone of  the  toe.   The
metatarsal bones also have
flat articular  surfaces at
the  posterior  extremities
for connecting  them with
each other.
   There are fourteen muscles attached to these bones, viz. the
seven interossei and transversales pedis, common to all; the
tibialis anticus and  peroneus  longus are  attached to  the first
metatarsal bone ; the adductor pollicis pedis to the second  ; the
peroneus  brevis, adductor, and flexor brevis minimi digiti, to
the fifth.
 
OF THE  LOWER EXTREMITY.           77
                   BONES OF THE TOES.

  There are fourteen bones of  the toes :  two to the great toe,
Fig. 74, b, c;  three to each of the other toes, Fig. 75, b, c, d;
their division and arrangement are similar  to that of the fingers.
  There are  nineteen  muscles attached  to the phalanges  of
the toes, viz. on the upper surface the extensor proprius pol-
licis and extensor longus, et brevis digitorum pedis, and seven
interossei.   On the lower  surface, the flexor longus et brevis,
and abductor pollicis,  the flexor longus et brevis digitorum
pedis, and four lumbricales.
                     SESAMOID BONES.*

  Besides  the bones we have  described, there are others sel-
dom preserved in the skeleton ; such  are the sesamoid bones,
which are very small, and  found at  the roots of the first joint
of the thumb and of the great toe.  These are under or rather
in the flexor tendons: they serve as pulleys for increasing the
angle of insertion, therefore add considerably to the force of
the muscles, and protect the articulations.
  These bones give insertion  to  the flexor brevis pollicis
manus, and the flexor brevis, adductor  et  abductor pollicis
pedis.

  * Because  they resemble the grains of sesamum, or Indian corn.  This
term occurs in several parts of descriptive anatomy.  " Sesamoid bones are
sometimes found at the origin of the gastrocnemii muscles, and occasionally
they are connected with the ossa pubis." — Monro. 
78
OSSEOUS  SYSTEM
the tongue bone.   Os hyoides.
      Fig. 76.          Fig.  76.    There  is another  bone not
                   immediately connected with the skeleton,
                   situated at the root  of the tongue, the os
                   hyoides.*   It  serves  for the attachment of
                   the muscles  of the tongue, and of degluti-
                   tion; a, a, the great cornua;  b, the smaller
        c          cornua; c, the basis.
  The os hyoides is not immediately connected with any other
bone, but is  kept  in its  situation by numerous muscles and
ligaments.
  There  are ten  muscles  attached   to  this   bone,  viz.  the
hyo-glossus,  constrictor pharyngis  medius,  sterno-hyoideus,
omo-hyoideus,stylo-hyoideus, genio-hyoideus,  thyro-hyoideus,
genio-hyo-glossus,  digastricus, and the mylo-hyoideus.
* So called from its resembling the Greek letter v. 
OF  THE TEETH.
79
CHAP.  VI.
                       THE  teeth.

  The  teeth  are  the most solid parts of the body; in their
formation they bear a certain analogy to the homs of animals,
and thus differ in many respects from the bones.   Some anato-
mists have described them as an  appendage to the skin, since
they are, in fact, exterior to it, and  are exposed  in  a greater
part of their surface to the contact of the air, and to the me-
chanical and chemical action of bodies.  The greater part of
their surface is inclosed in  alveoli or sockets, which tightly
embrace  them, and form  the articulation termed  gomphosis.
That part which is thus contained in the socket is named the
root;  the middle, which is somewhat contracted, is the  neck;
and all above,  the crown.   All the teeth have a form more or
less elongated, terminating in a  pointed manner, and in  this
point or end of the  root is a small hole.   This  opening leads
to the hollow of the tooth or dental cavity, an excavation which
extends from  the point of the root to  the crown ; and this
cavity represents the  form of the tooth, and lodges its vessels
and nerves.
  The teeth, when  all are developed, are thirty-two in  num-
ber, sixteen in each jaw.
               STRUCTURE  OF THE TEETH.

  They are formed  of two  substances:  one exterior, called
enamel; the other interior, and of the same texture as bones. 
80                OSSEOUS SYSTEM
                  ENAMEL OF  THE TEETH.

   The enamel is only found  round the crown of  the  tooth;
it covers the whole  surface of the crown, is moulded exactly
upon it, and thus represents all its inequalities.   It is thickest
on that surface where trituration takes place, and  diminishes in
this  respect towards  the neck.  This disposition is a protection
to the surface which is most worn in mastication.  The fibres
of the enamel are small, parallel  to each other, and perpendic-
ular to the  surface of the  tooth ; by this arrangement  the
enamel is not liable to scale off, and is better calculated to re-
sist attrition.  In Fig. 77, may be seen the  enamel, marked a,
and  extending to b.


        THE  OSSEOUS  SUBSTANCE  OF THE TEETH.

   This forms the most considerable portion of the tooth, as
the whole of the  root and the interior of the crown.  It is com-
posed  of an exceedingly dense and compact tissue,  bearing an
analogy to ivory; for it  has  no  cancelli, and its fibres, when
seen by the  assistance of a  microscope, appear concentric,
parallel to  the surface of the tooth.
   By  chemical analysis, the osseous substance gives nearly  the
same results as the other bones, with the exception of a small
quantity of fluate of lime.
   Like the medullary  organs of bones, the  central part of the
teeth contains a soft spongy substance, formed by  a network of
vessels and nerves.  The vessels  are derived from the internal
maxillary artery ;  the nerves, from the second and    Fig. 77.
third branches of the fifth pair.  Fig. 77, is a sec-
tion  of an  incisor and molar  tooth, showing the
cavity which contains the nerve and vessels mark-  c
ed c, c.
 
OF THE  TEETH.
81
                    CLASSES  OF TEETH.

   The teeth  are  divided  into  three  classes: incisors,  canine
 teeth,  and grinders.


                         INCISORS.

   The front or cutting teeth are eight in number, four in each
 jaw.   They vary  from  the others in  the  form of the  crown,
 which  is like  a  wedge.  They are convex  in  front, concave
 posteriorly.   The layer of enamel which covers the  crown
 is thinner behind than in  front.   The roots  of  these teeth
 are always  single, very long,  and of a  conical form, slightly
 compressed  at  the sides,  and a little thicker  before  than
 behind.
   Fig. 78,  shows a  front, and  Fig.   79, the    Fig- 78, 79.
 profile  of  an incisor.   The  lower incisors are
 smaller than the  upper, their  roots larger, and
 laterally  more  compressed, sometimes  deeply
 furrowed.

                     CANINE  TEETH.

   These are  called also cuspidati, from  their  being spear-
 pointed.  There are two in each jaw,  placed  next in order at
 the sides of the incisors.   They have each but  one root,
 which  is  longer than the corresponding  portion of any of the
other teeth.    Fig. 80,  the front,  Fig. 81, the
profile.   The  canine teeth of the upper  jaw
have longer  roots than those of the lower,  and
are vulgarly  called eye-teeth, and those of the
lower jaw stomach-teeth.
   vol. i.             8
 
82
OSSEOUS  SYSTEM
                      THE GRINDERS,

   Or molar teeth, are twenty  in number, ten in each jaw, five
on each side.
   The  first  two  pairs  of grinders  are  called  bicuspidati.
Their crowns are surmounted by two conical
tubercles ; the root of each is generally sim-     s"
pie, but has  a well-defined  groove on  each
side  of its lateral surfaces.  Fig.  82,  a front
view, and Fig.  83,  the profile  of a  small
grinder.
   The next three, which  terminate the row, are called multi-
cuspidati.   They are remarkable  for  their great  size, and on
the surface of their crowns are four pyramidal tubercles, sepa-
rated by very distinct grooves ; the roots are divided into two,
three, four, or five parts or fangs,  each of which  presents an
aperture for the passage of the dental nerve and vessels.   Fig.
84, a view of a large grinder.   The root  of the     Fi   84
last grinder, (dens sapientia,)  in the lower jaw
is simple,  short, and conical; but in the  upper
it is generally divided into four short roots.

           OF THE FORMATION OF  THE TEETH.

  The teeth  are formed in a manner different from that of any
other  part of the body, and their developement presents many
remarkable phenomena.
  Before they are visible, they are formed in the interior of the
maxillary bones.   They are developed in small rounded sacks,
which are composed of  two  membranes; both  these mem-
branes are vascular, according to  Meckel  and  Fox, but the
external is the more so.  The  internal membrane is  the firm-
est, but thinner  than  the external ; its  connexions  with the 
OF  THE  TEETH.
83
teeth are more intimate, for strictly speaking, this is the forma-
tive organ.  The  dental vessels branch out  on it; and when
they are injected, it appears entirely red.  The external is of a
more spongy, looser, softer, and thicker texture, than the in-
ternal ;  it is continuous with the gums, lines the interior of the
alveoli, and forms their periosteum.
   At the first, these small sacks simply inclose a reddish fluid ;
but at about  the fourth  month of pregnancy,  there  appears
from the base of the internal membrane a small body, which  is
vascular and  soft.   This is the germ, or  pulp  of  the  tooth.
Numerous nerves and vessels, supplied  by the internal  mem-
brane, ramify in this pulp, which gradually assumes the appear-
ance of a tooth, this being the nucleus around which a tooth  is
moulded,
   The ossification of  the  tooth commences about the middle
term of pregnancy, and begins on as many points of the pulp
as the future tooth will have eminences on its surface ;  thus the
incisores and cuspidati commence  with one point, and the mo-
lares  with several.  The  several  points  increase  until  they
come in contact, then the tooth grows as an entire body.   The
pulp elongates at its base to  form the root.  In  those teeth
which have only one root, a conical shell of bone is formed
around the pulp, which continues to increase in length in pro-
portion as the ossification advances ; while in those which have
several roots, a division of the pulp takes place at  this part into
a corresponding number of processes.
   The outer lamina of bone is first completed ; and then lam-
ina after lamina is deposited, one  within the  other, the  pulp
still receding, until at length there remains only the permanent
cavity of the tooth, lined with  its  proper membrane, and filled
with the remaining portion of the pulp, which  now  serves as
the bed upon which the vessels and nerves  ramify previously
to their entering the bony substance of the tooth. 
84
OSSEOUS  SYSTEM
   The secretion of the enamel begins  shortly after the devel-
opement of the bony matter;  this substance is secreted by the
internal  face  of  the internal  capsule which envelopes  the
crown of the tooth, so that it  is moulded exactly to  the pro-
jections and  depressions  on  that  part.   The fluid which is
poured out from this internal membrane is thickish, and is soon
consolidated  into a  dark chalky substance, which  afterwards
becomes white and  hardened by more perfect crystallization.
This  is  the enamel; but at an early period this enamel  is not
very hard, and can be  easily separated, and can  in its perfect
state be readily detached  by heat.   The glandular apparatus
which forms this substance is not demonstrable.
               OF THE DECIDUOUS  TEETH.

   Infants have teeth, which  are the deciduous or milk teeth,
twenty in number, ten in each jaw, five on each side, viz. two
incisors, one cuspidatus, and two molares.   These commence
to appear ordinarily about  the  sixth month, and generally in
pairs, those of the lower jaw first, and then the similar ones in
the upper; and the whole  twenty  appear at about the thirtieth
month.
               OF THE PERMANENT  TEETH.

  The deciduous teeth drop from the gums, and are followed
by the permanent;  and the whole process of dentition is not
completed until about the  age  of twenty years, the last ap-
pearing being the dentes  sapientiae.   These permanent  teeth
are developed, and appear nearly in the same order as the milk
teeth. 
OF THE  TEETH.
85
  Nature has limited the duration of life in the teeth more than
in the other bones.  The power of nutrition becomes gradually
enfeebled in these organs,  and they perish by  their nutritious
foramina being obliterated.  Being  no longer retained  in  their
alveoli by any organic connexion, they become loose and fall
out; their sockets are absorbed.  But the tone of the stomach
being weakened naturally at this advanced period of life, man
is thereby reduced to feed upon soft substances, accommodated
to the languid state of the gastric powers  and the loss of the
teeth.
                      CHAP. VII.

                THE MEDULLARY  SYSTEM,

                OR THE MARROW OF BONES.

  I shall first describe  the deposition  of marrow  occupying
the cellular structure of the short and flat bones,  and  the ex-
tremities of the long bones.   The medullary membrane of this
structure appears to be a continuation and expansion of the ves-
sels that penetrate the foramina, and which, on reaching the in-
ternal surface of the spongy part of the bone, ramify ad infinitum,
and unite a thousand different  ways.   Their interweavings
give to the interior of the cellular tissue its peculiar florid aspect,
which is more evident as we examine it nearer to the period  of
infancy, because the  vascular system of bones is then very 
86
MEDULLARY  SYSTEM,
conspicuous, while it gradually contracts and fades away as age
advances.*
   This vascular extension can be distinctly seen in the injected
bone, forming, as it  were,  a membrane throughout the innumer-
able cellulae of the bone ;  and the exhalation of the  medullary
fluid or marrow, which fills the interstices I have just mentioned,
seems  to proceed from this vascular net-work.
   The medullary system of the middle  of long bones, whose
largest cavity it fills, somewhat differs  from the preceding, in
having less vascularity ;  while  a thin transparent membrane
lines the  whole cavity, and is  repeatedly folded upon itself,
giving  rise to numerous extensions, some of which surround the
very minute filaments of the cancelli of the sides of the cavity,
others  pass from the  one  side  of the membrane to  the other
without adhering  to any ossified portion,  the  whole of which
forms  spherical cells  filled  with  marrow, and when  viewed
through a microscope  resembles a cluster of pearls.
   The medullary system of bones,  in a healthy state, pos-
sesses  little sensibility, or  only  such a  degree of organic sensi-
bility as is indispensable to  its functions.   As a proof of this,
the marrow may be  irritated in a living animal without any signs
of feeling being expressed.  The sawing of the skull with the
trephine, and the division  of  the bone  in  amputations, are not
attended with pain.
   Marrow, according  to Berzelius, is a species  of fixed oil,


  * The blood vessels of bones are much more numerous than we should ex-
pect from their color, for the earth  of the bone conceals them; and hence
they are not apparent even after being filled with a red injection, until by
immersion in diluted muriatic acid, the earth of the  bone has been destroyed.
When a bone has been thus prepared, and put into  oil of turpentine, its vas-
cularity is shown to great advantage. 
                 OR  MARROW  OF BONES.               87


possessing peculiar  properties, and something like butter.   It
consists of the following ingredients :

      Pure marrow or fixed oil,  ....           0 96
      Skin and blood vessels,  ....              0 01
      Albumen,          ~)
      Gelatine,            I
      Extractive,          f......0,03
      Peculiar matter,      \
      Water,.      .            ......1>03

  The use of the marrow  in bones, I believe to be the same as
the use of the fat in or about  other parts of the human  body,
viz.  it is a mere deposit of superfluous nutritious matter. 
ART.  II.
                         CHAP. I.

CARTILAGINOUS SYSTEM, OR THE  GRISTLE  OF  BONES, ETC.

   In order to render the motions of the bones  on each  other
more easy, the ends are incrusted with a substance of a white
or pearly color, hard, yet very elastic.  This  is a  peculiar sub-
stance found in various parts of the body, especially on the ar-
ticular surfaces of bones, the end of the nose, the edges of  the
eye-lids, the ear, the wind-pipe  and  air passages, the ends of
the ribs, etc.   Cartilage  forms  a considerable  share  of those
parts where flexibility and firmness are to a certain degree  com-
bined, in order that  the organ may, after being bent, recover its
determined form.
   The cartilaginous tissue is a net-work of fibres,  so closely
interwoven that at first sight  it appears completely homogene-
ous and  formed of a mass of albumen without  any particular
order or direction ; however, a more attentive examination will
discover longitudinal fibres, crossed by others in  a transverse di-
rection.  The  fibrous arrangements of the cartilage of joints are
perpendicular to the surface of the joint, and  after maceration
for six or eight weeks, may be observed to be placed at right
angles in respect to the bone  to which they are united.
   The surfaces of cartilages  which are in contact are finely
polished, that by its smoothness  it  may facilitate the sliding
motion of the two bones on each other.  The elasticity reflects
a considerable part of the motion, which by  a little  yielding 
CARTILAGINOUS  SYSTEM.
89
becomes extended, and  thus  moderates  the  effects of violent
shocks to which the limbs are often liable in active exertions.
  The elasticity of cartilage is  very  conspicuous, particularly
in youth and adult age.   If the blade of a scalpel is thrust into
cartilage, the two  edges  of the division will re-act upon it, and
repel the instrument; when pressed  it becomes  flattened, but
resumes its primitive shape  as soon as  the cause of compres-
sion is removed.   Thus  has nature placed cartilages where, to
answer particular  purposes, it is requisite that  a  physical prop-
erty should be united to  the vital powers, as in the larynx; and
in the nasal partition, to produce a kind of vibration  in the pass-
age of air; at the  ends of the ribs, to  maintain that kind of con-
tortion indispensable to mechanical respiration ;  and in the ar-
ticular extremities, to resist the effects of external violence, for
in those  situations they serve as a kind of elastic cushions, yield-
ing on compression, and  regaining their form on  that compres-
sion being removed.
  During  life  this elasticity of cartilage  is most apparent,
although it remains after death.
  The cartilages are divided into articular, interarticular, con-
necting cartilages, and cartilages of particular cavities.
  Articular cartilages cover the surfaces of bones in the mova-
ble joints.
  Interarticular cartilages are interposed between the ends of
bones to form a movable socket, which,  like the  friction wheels
of machinery, aid  the motion of the joint.
   Connecting cartilages unite the articular surfaces of bones by
an immovable union, as  in the sutures of the skull, the connex-
ions of the bones of the pelvis, etc.
   Cartilages of cavities  are such as  form  the  larynx,  trachea,
part of the nose, etc.
  The number and the thickness of cartilages interposed between
each bone, renders the acts of running, jumping, and perform-
ing other feats of activity, much  more easy.  Severe blows on
   vol. i.            13 
90
CARTILAGINOUS  SYSTEM.
 the ribs do not break them, for their  cartilaginous extremities
 recoil,  and yield  to the  violence;  as, however, in  age the
 quantity of cartilage diminishes,  and some  cartilages  entirely
 disappear, so the bones lose that  elastic medium, and their ex-
 tremities are unyielding and inelastic, and any degree of violence
 is frequently attended  with  fracture.   For instance,  a child
 falling twice its height, from the  elasticity of its frame would
 receive little or no injury ;  the  condition of old age is very dif-
 ferent : the bones are consolidated, and a fall of the same na-
 ture might prove most disastrous.
   The blood-vessels, nerves, and absorbent vessels  of cartilage,
 are so  small as to elude  observation;  but  there cannot be a
 doubt of their existence, of which there is the clearest evidence
 from the phenomena of its inflammation and absorption in disease;
 but in  its natural state  its  vitality is very obscure, sensibility
 and contractility being such only  as are necessary for its growth
 and nutrition.   When divided, if the edges be brought into
contact, after a length of time  re-union  will take place, as 1
have observed  in wounds of the cartilage of the nose and of the
ear. 
ART.   III.
                        CHAP.  I.

                     FIBROUS  SYSTEM.

  All the fibrous organs are absolutely of a similar nature, and
the same fibres contribute to the composition of all the forms ;
yet, in their arrangement, they vary in an astonishing degree ;
and it is the variety in their form, situation, and office, that has
caused them to be denominated and designated by  the  names
of tendons, aponeuroses,  ligaments, etc.
  The fibrous parts of the human system everywhere display a
whitish, or shining silvery appearance.   The  basis is a dense
fibre of a peculiar nature, rather elastic,  insensible,  hardly ad-
mitting of contractibility, sometimes arranged in juxta-position,
and assembled together in bundles parallel to each other, as  in
the tendons and ligaments; at other times they are  intersected
and spread out in sheets, the fibrous web of which turns in di-
versified directions, as in the membranes, the capsules, the fibrous
sheaths, etc.
  The strength of the fibrous tissue renders every organ it com-
poses fitted to sustain  the utmost efforts its uses require.  Thus
the ligaments strongly retain the articular surfaces in  apposition.
The aponeuroses prevent the displacement of the muscles,  and
give attachment to their fibres.   The tendons, incessantly ex-
posed to the contraction of the muscles, are placed between the
power they conduct and their attachments, offering a resistance 
92
FIBROUS  SYSTEM
that frequently proves stronger  than the  bone itself.  For by
muscular exertions the patella, the olecranon, and the os calcis,
have been sometimes  fractured.

   The several forms of the fibrous membranes are —
   1st.  Those which include the periosteum, the dura mater,
the tunica  sclerotica, the  tunica albuginea, the  proper mem-
branes of the kidneys, spleen, etc.   They are generally intend-
ed to cover certain organs, to the texture of which they con-
tribute.
   2nd.  The fibrous capsules, very different, as will be shown,
from the synovial surfaces, are a kind of cylindrical bags  that
are found around some articulations, especially around those of
the humerus and  the  femur,  where  they are connected with
the scapula and ilium, inclosing both their articular surfaces.
   3d.  The fibrous sheaths are intended to confine the tendons
in their situation, particularly on their passing over the bones,
where they undergo  flexion,  as in  the fingers and toes; for
without this contrivance they would  be liable to deviate,  and
thus transmit  but imperfectly muscular motion.   The  fibrous
sheaths have been divided into two  species ;  those which con-
fine a number of tendons, as at the  wrist, instep,  etc., others,
like those of the fingers, are intended for an isolated tendon, or
for the reception  of two only.
   4th.  The aponeuroses are a kind of fibrous canvas, more or
less extended, and always connected with locomotion, and dis-
posed in such a manner that  they sometimes form coverings for
different parts, and at other  times  they  provide  the muscles
with points for insertion.

   The fibrous organs formed in fasciculi are —
    1st.   The tendons found  at  the extremities, or  in the
centre of muscles ;  these are  either single,  in the form  of ex- 
OF  THE  PERICHONDRIUM.
93
tended strings, or compound, as in  the rectus femoris, flexors,
etc.
  2d. The  ligaments which secure  the articulations, around
which they are placed;  these are formed of regular fasciculi,
as the ligaments of the jaw, elbow, knee, etc., or of irregular
fasciculi, as those of the ribs, pelvis, he.
                        CHAP. II.

                     PERICHONDRIUM.

  This is a membrane perfectly similar to  the periosteum ;  it
covers the cartilages in the same  manner, and serves the same
general purposes to cartilage as the  periosteum does to bone.
The perichondrium of the larynx, the ribs, &.c, is a thin tissue
of fibres, intersected  in every direction, is highly  vascular, and
can be injected.  But the vessels of this membrane, where  it
covers the articular surfaces, cannot be demonstrated ; indeed  it
adheres so closely as to appear like the cartilage itself, although
it can be proved  to  be a reflection of the synovial membrane
of the joint. 
94
FIBROUS SYSTEM
                        CHAP. III.

                     THE LIGAMENTS.

   The ligaments are those fibrous substances which connect
the articular ends  of the bones  and cartilages, by which they
are all united into one admirable structure, the individual parts
of which are firmly maintained in such particular relative situa-
tions as are best calculated to admit with safety the numerous
motions that are required.
   The bones are united by strong investing membranes, and by
flexible and elastic bands, composed of dense  fibres intimately
interwoven with each other, and passing in different directions,
the greater number of which pass  in direct lines between  the
parts which the ligaments  connect.   The  ligaments then may
be described as an assemblage of strong fibres, firmly joining
together the articular surfaces of bones, and giving that secu-
rity which will prevent  displacement, and yet such a latitude
of motion  as  will admit of the easy movement  of one bone
on the other.
   The ligaments receive their supply of blood from the vessels
in  their  immediate  vicinity ; they  possess but  a very small
share of elasticity, and in a sound state are nearly destitute of
sensibility.  B re hat asserts that no nerves can be discovered
in them ; but Dr. Monro traced them distinctly into their sub-
stance, and we know under diseased  excitement  they are ex-
tremely sensible.


                  CAPSULAR LIGAMENTS.

   I have mentioned  the  periosteum as covering the bone;  the
same  periosteum, as  it were, is continued over the joint,  and 
OF THE  LIGAMENTS.
95
forms a loose bag termed  the capsular  ligament, which con-
tains the glaiiy fluid* with which the joint is lubricated.   The
capsular ligaments are strengthened by the addition of irregular
fasciculi of fibres which cross over  the joints  in different  direc-
tions ;  not to mention that the  further security of the joint is
provided for by the muscles and tendons which pass over  it.
                   LATERAL LIGAMENTS.

  These ligaments are strong skeins of fibres, firmly united to
the periosteum,  and passing  from one extremity of bone  to
another,  and  are always found in the hinge-like joints.   The
lateral ligaments  moderate, and  in  some  measure limit, the
movements of the joint.
             LIGAMENTS WITHIN THE  JOINTS.

  These ligaments are for giving additional strength, and regu-
lating the movements  of certain  articulations, as the  round
ligament of the hip, and the cross ligaments of the knee.
  These are  the principal species of ligaments of the  body ;
there are, however, others  that unite the bones which do not
move  on  each other,  as the os sacrum  and os innominatum.
There is also an elastic substance, which  is an antagonist to
the muscles, and by which they are  restored to their original
situation, or supported in it.   These sometimes form part of
the muscles;  thus  the head is supported by  a strong elastic
ligament appended to the muscles of the back.  In those ani-

  * The synovial membrane which produces this fluid must be distinguished
from the capsular ligament.  The former is  allied by structure and function
to the serous membranes, the latter to the fibrous. 
96
FIBROUS SYSTEM
mals which have long necks, this is particularly strong, as in the
ox and the horse ; for the head acting at the end of a long lever,
could not be  supported for any length of time, or would be in
danger  of dislocation, were it not for this elastic tape which
supports the  head without the  expense of muscular power.
Those ligaments usually  denominated interosseous ligaments,
placed between the radius  and ulna, tibia  and fibula, etc., are
simply  aponeurotic membranes,  serving for  the attachment
of muscles; and thus supplying the place  of  bones, save  an
unnecessary weight and incumbrance.
                      CHAP. IV.


            PARTICULAR  LIGAMENTS.

                LIGAMENTS OF THE  HEAD.

  These  may be  divided  into two  classes :  the  first  con-
nects the lower jaw  to the temporal bones ; the  second,  the
head to the neck.
             LIGAMENTS OF THE LOWER  JAW.

  The condyles of the jaw  are fixed to the  articular cavities of
the temporal bone by  a  capsular and two lateral ligaments,
with the addition of an interarticular cartilage. 
OF THE  LIGAMENTS.
97
CAPSULAR  LIGAMENT.
The capsular ligament consists of  dense fibres, which  are
Fig, 82.
superiorly attached to c, the
margin of the zygomatic emi-
nence, and  to  the fissure in
the  glenoid  cavity.    It  is
again attached  to the  edge
of b, the  interarticular carti-
lage, and  inserted  inferiorly
at a, into  the  neck  of the
condyle  of the  lower  jaw.
Fig. 82 exhibits  a section of
the joint.
INTERARTICULAR  CARTILAGE.
  This cartilage, b, forms a sort of movable cover over each
condyle of the jaw, separating the capsule into  two parts, by
its circumference adhering strongly to it.
INTERNAL LATERAL  LIGAMENT.
Fig. 83.
  This   ligament   is
attached  above  at   a,
the  edge  of the  gle
noid cavity ;  below  at
b, the  margin  of the
posterior  dental   fora-
men, in  the ramus  of
the jaw.
VOL.  I. 
98
FIBROUS  SYSTEM
               STYLO-MAXILLARY LIGAMENT.

  This ligament is extended from c, the styloid process of the
temporal bone, to e, the  angle of the jaw.

               EXTERNAL LATERAL  LIGAMENT.
                                             Fig. 84.
                                                a
   This  ligament   passes  obliquely
across the  capsular ligament, from a,
the zygoma, to the posterior part of b,
the  neck of the jaw.
LIGAMENTS CONNECTING THE HEAD  AND  NECK.

                                  Fig. 85.
  The  ligaments con-
necting the  head  to
the neck  may  be  ar-
ranged  as  follows: —
the capsular,  perpen-
dicular, and lateral lig-
aments.
               TWO CAPSULAR LIGAMENTS.

  These ligaments connect the condyles of the occipital bone
to the articulating cavities of the atlas.
 
OF  THE  LIGAMENTS.
99
          ANTERIOR PERPENDICULAR  LIGAMENT.

  A broad ligament attached superiorly to the anterior edge of
the  foramen  magnum, and  inferiorly to the ring  of  the atlas ;
its fibres extend some distance down the cervical vertebrae.


          POSTERIOR PERPENDICULAR  LIGAMENT.

  A broad and strong  ligament, extending from the posterior
edge of the occipital foramen to the upper vertebra of the neck.
Its  direction and attachments  are shown in Fig. 85,  from  a, a,
though a part of it is removed to show other ligaments,


                TWO  LATERAL LIGAMENTS.

  These ligaments, Fig. 85,  b, b, are seen extending from the
margin of the occipital foramen to the odontoid  process of the
dentata or second  vertebra.
                       CHAP.  V.

             LIGAMENTS OF THE VERTEBRJE.

  The spinal column is composed of numerous bones, so won-
derfully connected to each other, that motion is permitted to a
requisite extent, without the safety of the spinal marrow, or the
strength of the column, being in  the  least impaired.  Several
ligaments  are required to effect  these important  purposes:
these  differ  from each other in form and in use; some are 
100
FIBROUS  SYSTEM
common to all the vertebrae, others  are confined to two of
them, others again are peculiar to the cervical vertebrae.

               LIGAMENT OF THE SECOND VERTEBRA.

                  TRANSVERSE LIGAMENT.

  This is a strong fasciculus of ligamentous fibres, Fig. 85, c,
extending from one side of the articular process of the atlas to
the opposite  side; it is narrow at the extremities,  but  wide
in the centre, where  it  is. almost of  a cartilaginous hardness.
This  ligament  secures   the  odontoid process in  its proper
place,  and prevents the  possibility of its  pressure  on the spinal
cord.

            LIGAMENTS COMMON  TO ALL THE  VERTEBRJE.

                ANTERIOR COMMON LIGAM

   This is a  smooth, resplendent, broad
ligament, a, a, which extends along  the
anterior, convex surface of all the verte-
brae.   This ligament is  composed of par-
allel  fasciculi,  which,   however,  seldom
extend beyond two or three vertebrae,
where  one set terminates and  another
commences; thus its  entire   extent  re-
ceives  an access of fibres  from almost
every  vertebra it  covers.  It is attached
only  to the anterior part  of the spinal
column, though occasionally  it sends off
small oblique  processes, which are lost on
its  sides.   A  profile of this  ligament is
seen in Fig. 91, c.
[ENT.
a 
OF THE  LIGAMENTS.
101
POSTERIOR  COMMON  LIGAMENT.
somewhat similar to the anterior, except that it passes
        along the inner, concave  part of the bodies
        of the vertebrae, and terminates at the sacrum;
        a, the intervertebral fibro-cartilage, cut trans-
        versely ;  b, b, b, b, the part from which the
        arch of  the  spinal  canal is removed; c, c,
        the posterior vertebral ligament, situated be-
        hind the  bodies of the vertebrae, smooth and
        resplendent, broader  on a level with each
        fibro-cartilage than with the body of the ver-
        tebra.
           These are numerous short and strong liga-
        mentous fibres crossing each other obliquely,
        joining the vertebrae together upon the outer
        edges of the  vertebral substance called by
        Fyfe, crucial intervertebral ligaments.
INTERVERTEBRAL LIGAMENT.
                      Fig. 86, c, c, c, c, c.

  There is placed between the bodies of the vertebrae a pecu-
liar substance, described by most authors as a texture  between
cartilage and ligament, partakmg of the property of both, hence
sometimes very properly called intervertebral fibro-cartilage-
It is composed of white shining fibres, arranged in laminae of
different thicknesses, but in very regular order.   If this substance
is divided by a horizontal section,  its fibrous structure is very
distinctly seen, the laminae running in regular concentric circles, 
102
FIBROUS  SYSTEM
or rather the circle is a little concave posteriorly, corresponding
to the form of the articular surface of the bodies of the verte-
bra?.   Although the external laminae are of a cartilaginous firm-
ness, and offer great resistance on pressure, the internal lamina
are more soft and delicate,  and at a greater distance from each
other,  in the interstices of which there is a peculiar substance,
not so firm as cartilage, nor quite so soft as gelatin.  The small-
er circles of fibres  are gradually softer in their texture as they
approach the centre, where nothing is  seen except a nucleus
of semi-liquid or mucous form.   Thus each vertebra resting on
a sort of fluid fulcrum, or pivot, the motion to either side is easy,
and quickly performed.  The motions of the back bone or bones
therefore, are performed on an almost  fluid centre, surrounded
by a perfectly elastic medium, which remarkable  union of flat
surfaces admits of the requisite degree  of motion, and  prevents
injury  to the delicate texture of the spinal cord and  brain in
violent exercise.
                    LIGAMENTA  SUBFLAVA.

   These ligaments are of a pale yellow color ; they are attached
superiorly  and inferiorly to the  opposite margins of the arch
of the spinous processes of the vertebrae,  completing  those de-
ficiencies of the spinal canal which are observed in the skeleton
at the posterior part of the spine, and extending as far forwards as
the oblique processes, the articulations of which they strengthen.
These ligaments  possess great elasticity, yet resist   too much
flexion of the vertebral column. 
OF  THE  LIGAMENTS.
103
                INTERSPINOUS LIGAMENTS.

   The  interspinous  liga-
ments, Fig.  88, b, b, b,
are attached to  the  upper
and lower margins of each
spinous process.  Like in-
terosseous  membranes of
the fore arm and leg, they
present  an  extensive  sur-
face for the  attachment of
muscles, and  connect one
spinous process with anoth-
er.
                SUPRASPINOUS LIGAMENTS.

  The supraspinous ligaments, Fig. 88,  a, a, are extended
from the point of one spinous process to that of another, in the
whole line from the seventh cervical vertebra to the sacrum.
         LIGAMENTS OF THE OBLIQUE PROCESSES.

  The articulations of the oblique articular processes  of the
vertebrae are secured by a strong capsular  ligament,  composed
of short fibres, which permit but little motion, except between
the first and second vertebrae, the articular processes of which
are very large, and the  ligament allows of a considerable rota-
tory motion.
Fig. 88.
 
104
FIBROUS  SYSTEM.
                       CHAP. VI.

        LIGAMENTS  OF  THE  THORAX.

         LIGAMENTS OF THE RIBS WITH THE VERTEBRJE.

                  CAPSULAR LIGAMENTS.

  The capsular ligaments are attached to the heads of the ribs;
and as there are two articular  surfaces
to the head of  each rib,  so there are
two regular capsular ligaments, which
are  opened in  the figure, a, a; their
fibres are radiated, one portion of its
fasciculi being extended to the vertebra
above, another to that below.   The fibres of the capsule extend
along the bone for some way, and mix with their anterior com-
mon ligament.   The back of the rib is articulated to the trans-
verse process;  consequently  there is a capsular ligament be-
longing to this joint also.
                INTERARTICULAR LIGAMENT.

  The interarticular ligament, Fig. 89, b, is fixed to the cen-
tral projecting angle on the head of each rib, connecting  it to
the intervertebral substance.  This ligament has no existence
in the first and  two last ribs :  as  the capsular ligaments are
single, each has but one articular surface on its head, and is
connected with one vertebra only.
 
OF THE  LIGAMENTS.
105
              MIDDLE TRANSVERSE LIGAMENT.

  This ligament,  a,  consists of
irregular  fasciculi of fibres, which
occupy the interval between the
rib at c, and  the anterior surface
of the corresponding  transverse
process at b.   It cannot  be well s
separated from its  attachments.

             INFERIOR TRANSVERSE LIGAMENT.
Fig. 91.
  This ligament, e, e, is composed of  two fasciculi, the one
extending from the lower edge of the transverse process of the
vertebra to the upper edge of the rib above, near its articulation
with the body of the vertebra.   The other fasciculus is smaller,
and is attached to the base of the transverse process, and is ex-
tended to the head of the rib beneath.

            ANTERIOR OR RADIATED LIGAMENT.

  This ligament, Fig. 91, d, d, is formed of three  flat  fibrous
  VOL. I.               15
Fig. 90.
until  the  rib  is  forcibly 
106
FIBROUS  SYSTEM
fasciculi, which are fixed separately to the two vertebrae, and to
b, the fibro-cartilage ;  these strongly secure the rib, by conver-
ging and  attaching  themselves to  its  head  and neck.   The
eleventh and twelfth ribs,  however, in  this  situation, present
only a single order of fibres.


LIGAMENTS OF  THE  CARTILAGES  OF THE   RIBS  WITH  THE
                         STERNUM.

   The cartilages of the seven superior ribs are joined to b, the
sternum, by strong ligamentous bands
at a, which cover the  synovial mem-
branes ; although this articulation has
but a very obscure motion, it has a
regular  socket and  capsule.   These
cartilages are united to the ribs by sym-
physis, or an  immovable articulation.                  b
   The upper part of the sternum receives some  ligamentous
fibres from its articulations with the clavicles.   The sternum is
also covered, both on  its anterior  and posterior surfaces, by a
strong aponeurosis, which is inseparably  connected to the peri-
osteum ; its fibres are very conspicuous  anteriorly, and  resem-
ble tendinous bands, taking a longitudinal direction, and uniting
those portions of the bone  which in  young persons it  is found
to consist of.
   Some fasciculi extend beyond the margins of the sternum, and
are attached  to the  cartilages  of  the ribs.   The aponeurosis
which covers the internal surface of this bone is more smooth and
polished,  and its fibres take a longitudinal course.
   The xiphoid or ensiform cartilage is connected to the ster-
num by the above-mentioned aponeurosis, and has radiated lig-
amentous fasciculi connecting it with that  bone,  and with the
cartilage of the seventh rib.
 
OF  THE  LIGAMENTS.
107
                      CHAP. VII.

          LIGAMENTS  OF  THE  PELVIS.

  These consist of the ligaments  connecting the ossa  innomi-
nata, the sacrum, and coccyx.
LONG POSTERIOR LIGAMENT  OF THE ILIUM.

                  Fig. 93.
   This ligament is attached outwardly, at a, to the  posterior
superior spine of the ilium, descends obliquely inwards, and is
inserted, at d,  into the third and fourth transverse tubercles of
the sacrum ; g, the great sacro-sciatic  ligament.


               SHORT  POSTERIOR LIGAMENT.

  This ligament is attached inwardly in common with the pre-
ceding, and extends to the third tubercle of the sacrum, at c. 
108
FIBROUS  SYSTEM
              POSTERIOR LATERAL LIGAMENT.

  This is a narrow ligament, extending from the internal sur-
face of the same spinous process of the ilium, at a, to the lower
margin of the first division of the sacrum, b.
GREAT SACRO-SCIATIC  LIGAMENT.


             Fig. 94.
  This ligament is situated at the lower and posterior  part of
the pelvis ; it is of a triangular form attached superiorly  at a, a,
the posterior  and inferior iliac spine,  to  the fourth and fifth tu-
bercles of the sacrum, to the lower portion of this bone and to
the coccyx.  The fibres converge, and pass obliquely outwards
and downwards to be inferiorly attached at a, the tuber ischii. 
OF THE  LIGAMENTS.
109
            SMALLER SACRO-SCIATIC LIGAMENT.

  This ligament is attached inwardly at b,  b, to the margin of
e, e, the sacrum and coccyx ; its converging fibres are outwardly
inserted at b, into the  spinous process of the ischium.   The
figure shows the crossing of  the sacro-sciatic  ligaments  about
their centre, giving great support to the contents of the pelvis ;
these ligaments also give attachment to some fibres of the leva-
tor ani and coccygeus muscles.
  The coccyx is connected to the sacrum by a strong tendi-
nous aponeurosis,  e, e, which is  continued  down  from  the
tendons of the lumbar  muscles; beneath this are two  strong
ligaments, which  pass   from the  last spinous tubercle of the
sacrum to the first bone of the coccyx; and  there  is  also a
capsular ligament between the sacrum and coccyx.


             SUPERIOR ILIO LUMBAR-LIGAMENT.

  This ligament, Fig.  93, e, runs  transversely from the upper
edge of the ilium  to  the transverse processes  of the two  last
lumbar vertebrae.

             INFERIOR ILIO-LUMBAR LIGAMENT.

  This ligament,/*, is  situated immediately below the former,
runs the same course, and has nearly the same attachments.


                 ILIO-SACRAL LIGAMENTS.

  The anterior part of the surface of the sacrum and ilium
are mutually connected by  cartilage, the posterior by  strong 
110
FIBROUS  SYSTEM
 ligaments, which pass in  every direction from one bone to the
 other.   This synchondrosis in front, and syndesmosis behind, is
 so very  strong, as to  prevent any motion  between the ilium
 and sacrum.

               SYMPHYSIS  OF THE OSSA PUBIS.

   The fibro-cartilaginous  connexion of these bones consists of
 concentric layers, which unite the two oval surfaces which the
 ossa pubis present anteriorly, and they  are  further  secured by
 strong ligamentous  fibres, crossing from one side  to the other;
 an examination of which must lead us to  deny  the possibility
 of any separation taking place in parturition.


           MEMBRANE OF  THE  THYROID  FORAMEN.

   This  is  a fine, smooth, tense  membrane, attached to the
 circumference of this  opening; it consists of two laminae, the
 use of which is to give origin to the external  and internal obtu-
 rator muscles.

           LIGAMENT OF FALLOPIUS OR POUPART.

  This has been considered as a tendon at  the  inferior border
of the external  oblique muscle  ; it may, however,  be strictly
considered as a  distinct ligament, extending from  the anterior
superior spinous process of the  ilium  to the ossa pubis.*  To

  * It has  three insertions.
  1st. Insertion into the symphysis  pubis and pubis of the opposite  side.
This forms the superior column or pillar of the abdominal ring.
  2d. Insertion into the spine of the pubis, forming  the inferior column or
pillar.
  3d. Insertion passes backwards to be attached to  the crest of the pubis,
and is the ligament known by the name  of Gimbernat's. 
OF  THE  LIGAMENTS.
Ill
its upper  edge the abdominal muscles  are  attached, and to
its lower the fascia  lata  of the thigh.   It is subtended like a
cord across the cavity between the  spine  of the ilium and the
pubis, thus protecting the femoral vessels and  nerves as  they
leave the pelvis along with the psoas and iliac muscles.
                     CHAP. VIII.

      LIGAMENTS OF THE SUPERIOR EXTREMITIES.

  Under this head I shall describe the ligaments of the clavicle,
shoulder, arm, fore-arm, wrist, and hand.


        LIGAMENTS  OF  THE  CLAVICLE.
INTERCLAVICULAR  LIGAMENT.

           Fig. 95.
  The interclavicular ligament, a, is a fasciculus of strong liga-
mentous  fibres, extending in a transverse  direction above the
sternum,  from one clavicle  to the other, connecting  them  to-
gether, and attaching those bones to the sternum. 
112
FIBROUS  SYSTEM
               STERNOCLAVICULAR LIGAMENT.

  This ligament,  b,  forms an  imperfect  capsule, its  fibres
extending over the articulation from the triangular or sternal end
of the clavicle, to  the anterior and posterior  surfaces of  the
sternum ;  a few fibres are also attached to the first rib.
               INTERARTICULAR CARTILAGE.

   This is an apparatus similar to the articulation of the jaw; it
is  a movable  cartilage, a,
thick  at its  circumference,
and thin in the centre, adapt-
ing the extremity of one bone
to the other.   It is  fixed  at
one edge to  b,  the clavicle;
and the capsular ligament is
adherent  to  the root  of the
border.  In  the  figure  this
ligament is cut,  and  the bones separated,  to exhibit the car-
tilage.


               COSTO-CLAVICULAR  LIGAMENT.

   The chasm between  the clavicle and first rib is closed by
this ligament, Fig. 95, c.  It is of a rhomboidal figure, extend-
ing from the inferior surface of the clavicle near its sternal end,
to the upper and anterior part of the cartilage of the first rib.
Some fibres also adhere to the interarticular cartilage.
 
OF THE  LIGAMENTS.
113
              ACROMIOCLAVICULAR LIGAMENT.

  This ligament, Fig. 97,/ is attached to the superior and outer
rough surface of the clavicle, extending a considerable  length,
to connect the corresponding surface of the acromion scapulae.
              C0RAC0-CLAV1CULAR  LIGAMENT.

  This ligament, d, is very strong, and is formed by  a conoid
fasciculus of diverging fibres fixed to the tuberosity on the outer
extremity of the inferior surface of the clavicle, and is extended
to the internal part of 6, the coracoid process of the scapula.
        LIGAMENTS OF  THE SCAPULA.

                 ACROMIO-CORACOID LIGAMENT.

  This ligament, e, is attached to the superior convex  surface
of b, the coracoid process ; its fibres, which are thick and strong,
ascend obliquely outwards, and are inserted  into/, the  inferior
surface of the acromion scapulae.
                   CORACOID  LIGAMENT.

  This  is merely a ligamentous chord, g, extended over the
semilunar notch so as to convert the latter into a foramen.   The
supra-scapular vessels and nerves pass under this ligament.
  VOL. I.             16 
114
FIBROUS  SYSTEM
LIGAMENTS BETWEEN THE SCAPULA AND HUMERUS.

                 CAPSULAR LIGAMENT.

                        Fig. 97.
   This ligament, h, consists of an oblong sack, surrounding the
 neck of the scapula, and inclosing the  head of  the humerus;
 the capsule is perforated by i, the long  tendon  of the biceps
 muscle passing through it, i. e. between the fibrous and syno-
 vial membrane, to be attached to the edge of the glenoid cavity
 of the scapula.


                   ACCESSORY LIGAMENT.

   The accessory ligament is  formed of a strong  fasciculus at-
 tached to the  coracoid  process of the  scapula,  and  directing
 itself forwards and outwards ; it  is  expanded  over  the upper
 and  anterior part  of  the joint, giving  the capsule  additional
 strength.
  The capsular ligament forms but a loose and weak  connex-
ion between the humerus and shoulder, were it not for the sev-
 eral muscles whose tendons  adhere to  and strengthen it;  the
infra-spinatus and teres  minor by their  united tendons cover 
OF THE  LIGAMENTS.               115
it externally, the supra-spinatus superiorly, and the subscapularis
internally ; in addition to these muscles, the deltoid, the coraco-
brachialis, and biceps,  all co-operate  in no small degree to
strengthen the connexion between these two bones.
  There is a fibro-cartilaginous rim which increases the  depth
of the glenoid cavity of the scapula, termed  by Cloquet the
glenoid ligament; although I consider it merely a cartilaginous
border to the socket of the scapula, not only useful in render-
ing the socket deeper, but for preventing fractures of the rim in
robust exercises,  to  which, were it  bony,  it  would  be very
liable.
LIGAMENTS BETWEEN THE HUMERUS AND BONES OF THE ARM.
CAPSULAR  LIGAMENT.
  The capsular ligament, a, envelopes the entire articulation of
                 the elbow joint; on the posterior surface of
                 the humerus it is attached to the margin of
                 the great sigmoid notch which receives the
                 ulna, and passing obliquely downwards be-
                 neath the condyles, round to the fore part of
                 the bone, descends to the ulna ; it is inserted
                 into the olecranon process, into  the margin
                 of the sigmoid cavity, and into the  orbicular
                 ligament which connects  the radius to the
                 ulna.   Externally this capsule is  rough, and
                 strengthened by bands which run in irregular
                 directions ; internally it is lined by the smooth
                 synovial membrane.  It is very  loose  ante-
riorly  and posteriorly, to  admit of a free flexion and extension;
 
116
FIBROUS  SYSTEM
but on either side it is tense, and strengthened by lateral liga-
ments, which prevent any lateral motion.
              EXTERNAL LATERAL  LIGAMENT.

  This ligament, Fig. 98, e, is attached to the most prominent
point of the external condyle, and descending expands itself so
as to be inserted into /, the orbicular ligament, and not into the
radius : the rotatory motion  of the fore  arm on the  humerus is
thus permitted.
INTERNAL  LATERAL LIGAMENT.
  Th:s ligament, b, is longer and broader than the preceding,
      Fig. 99.          and extends from the internal condyle
                      of the humerus, in a radiated direction,
                      to the inside of the coronoid process of
                      the ulna; a few fibres descend a little
                      backwards,  and  are  attached  to  the
                      margin  of the olecranon.   The  lateral
                      ligaments adhere so firmly to  the cap-
                      sular, that they appear to form part of
                      its texture.
                         The two ligaments called the ante-
                      rior  and posterior, are  both thin  and
                      irregular fibrous bands, the one placed
in front and the other  behind the articulation ; the  former is
fixed in front to the internal condyle of the humerus, and to the
annular°ligament of the radius ; the latter to the posterior  part
of the external and internal condyles of the humerus.
 
OF  THE  LIGAMENTS.
117
     LIGAMENTS BETWEEN  THE RADIUS AND ULNA.

                   SUPERIOR ARTICULATION.

              ORBICULAR  LIGAMENT.

  This ligament, Fig. 98, / surrounds  the upper extremity of
the radius, and with the  small  sigmoid cavity forms a sort of
ring, in which the radius turns with ease.  The  superior mar-
gin is attached  to the capsular  ligament, the inferior  to the
neck of the radius.  Its use is  to confine the head of the  radius
in its proper situation.
    ANTERIOR AND  POSTERIOR  ACCESSORY LIGAMENTS.

  These are ligamentous  fibres which run in various directions
upon the fore and back parts  of the joint, and  contribute ex-
ceedingly to  its strength ;  the  anterior  extending from the
coronoid process to the orbicular ligament;  the  posterior  from
the  lower border of that ligament to the lateral smooth surface
of the olecranon.
             MIDDLE ARTICULATION.

                      ROUND LIGAMENT.

             CHORDA TRANSVERSALIS CUBITI.

  This is a small round fibrous chord, Fig. 99, c, extending from
the outer side of the tuberosity of the ulna to  the radius, a little
below the tubercle for the insertion of  the biceps.   It prevents
too great a degree of supination of the radius. 
118
FIBROUS  SYSTEM
                  INTEROSSEOUS  LIGAMENT.

   This ligament occupies the space which exists  between the
radius and ulna, although it is not quite so long, being deficient
at its upper part.   It has the appearance of a thin aponeurotic
resplendent membrane, extending from the  sharp edge of the
radius  to  the  opposite edge of  the  ulna.  It  constitutes a
medium of connexion between these bones, and affords an ex-
tensive surface for the attachment of muscles.


             INFERIOR  ARTICULATION.
                  INTERARTICULAR  CARTILAGE.

          CART1LAGO  INTERMEDIA TRIANGULARIS.

   This is a fibro-cartilage, placed  transversely  between the
lower extremity of the radius and  ulna ; the superior surface is
continuous with the cartilaginous   covering of the end of the
radius, and together with  this bone completes the cavity for
receiving the upper part of the carpus ; each extremity is con-
nected by strong ligaments  to the  radius  and carpus.   The
apex of  this  cartilage is  firmly  attached  to  the  depression
which separates the styloid process of the ulna from  the articu-
lar surface of that bone.

            CAPSULAR OR  SACCIFORM LIGAMENT.

   This ligament passes from the  radius  to  the ulna, forming
between them a very loose cul-de-sac, which allows the radius
to turn upon the ulna.

              EXTERNAL LATERAL LIGAMENT.

   This ligament, Fig.  100, extends from  the styloid process of
the radius to the  scaphoid  bone and annular ligament of the
carpus. 
                  OF  THE LIGAMENTS.               119


              INTERNAL LATERAL LIGAMENT.

  This ligament, b, extends  from  the styloid process  of the
ulna to the cuneiform bone  and annular ligament of the carpus.
There are other and more delicate fibres, termed  the  anterior
and posterior ligaments, and there is a synovial membrane for
the whole articulation.
               LIGAMENTS OF THE CARPUS.

       LIGAMENTS OF THE FIRST  ROW OF THE CARPAL BONES.

                      Fig. 100, a, b, c, d.

   The three upper bones of
the carpus are united  togeth-
er, 1st, by interosseous liga-
ments  placed in the  inter-
vals between the scaphoid,
semilunar,  and   cuneiform
bones; 2d, by dorsal liga-
ments extending transversely,
the one between the scaphoid
and  semilunar  bones,  the
other between the latter and
the cuneiform bone ;  3d, by
palmar  ligaments, c,  similar
to the preceding.  The  pisi-
form bone  is  articulated  to
the cuneiform by a loose cap-
sular or synovial membrane,
strengthened by some  irregu-
lar bands  of fibres.
Fig. 100.
 
120
FIBROUS SYSTEM
 LIGAMENTS OF THE SECOND ROW OF THE CARPAL BONES.

  These are united : 1st, by  dorsal  and  palmar ligaments,
three  on  either side, which extend inwards  and backwards;
and 2d, by  interosseous ligaments; of these  there  are only
two;  both are  irregular fasciculi,  intermingled  with adipose
tissue.
    LIGAMENTS  OF THE TWO ROWS  OF CARPAL BONES.

   1st. There  are two short lateral ligaments, the one external,
the other internal.   2d. Two fibrous fasciculi, one in front, the
other behind,  termed the anterior  and  posterior ligaments;
these last mentioned ligaments form a fibrous membrane, enve-
loping the  whole carpus.  3d. There is also a synovial mem-
brane  which  lines the surface, by  means  of which the two
rows of the carpal bones are in contact.  Lastly, we find at g,
two ligaments of the pisiform bone, connecting it to the cunei-
form bone and the metacarpal bone of the little finger.
        THE ANNULAR LIGAMENT  OF THE CARPUS.

  The annular ligament is situated on a  plane much  anterior
to that of the other ligaments of the carpus ; it is composed of
strong and tense  fibres, which  are  attached principally to the
cuneiform bone internally, and the trapezium  externally;  near
the latter, some of the fibres are also fixed into  the  scaphoid
bone, and assist in completing  the annular passage or channel
in which the flexor tendons of the fingers pass, covering and
confining them in their course. 
OF THE  LIGAMENTS.
121
                LIGAMENTS OF THE HAND.

  The  metacarpal bones are  very securely joined to the car-
pus, not only by their wedge-like surfaces, but also by strong
ligaments.


                   CAPSULAR  LIGAMENTS.

  These ligaments are seen distinctly surrounding  the upper
extremity of each metacarpal  bone, and are inserted  into the
opposite bones of  the carpus ;  they are  secured  by accessory
bands, which pass in  various directions.
            SUPERIOR TRANSVERSE LIGAMENTS.

  These  ligaments,  d, d, extend across the upper extremi-
ties of the four metacarpal bones, and are attached to each of
them.*


            INFERIOR TRANSVERSE LIGAMENTS.

  These  ligaments, e, e,  present exactly  the same arrange-
ment, connecting the inferior extremities of the four metacarpal
bones with each other, not indeed  so  closely as at the upper
end, for there is greater freedom of motion at the  lower than at
the upper part.  The metacarpal bones are also united to each

  *The capsular  ligament is the only ligament which connects  the tra-
pezium with the metacarpal bone of the thumb.  This joint, however, de-
rives much strength from a number of small muscles/around it, as well as by
accessory bands.
  VOL.  T.            17 
122
FIBROUS SYSTEM
other by a strong transverse aponeurosis, which is connected
with the sheath  of  the  flexor tendons, and  covers  the tendons
of the lumbricales and interossei muscles.
                LIGAMENTS OF  THE  FINGERS.

   The first phalanx or row  of the finger bones  is  attached
 to the  metacarpal  bones by  loose but strong capsular liga-
 ments,  which are  strengthened  anteriorly  by  a semicircular
 ligament embracing the anterior part of each articulation, and
 posteriorly by the extensor tendons,  which expand very much
 while  passing over these  articulations ; also at the sides  by
 lateral ligaments, / / which  are attached to slight depressions
 on the lower end of  the  metacarpal bones, and into  the con-
 dyles of the first phalanx.   Similar ligaments to these exist at
 the articulations of the finger  bones with each  other, viz. each
joint  has  an anterior ligament, two lateral ligaments, and a
 capsular ligament or synovial membrane.
   The flexor tendons also are confined in their course  along
 the fingers by circular and vaginal  ligaments.   The former
 adhere on each side of  the tendon  to the proper ligaments of
 the joint,  the latter inclose the flexor tendons of each finger in
 a  strong sheath: each sheath is  composed  of circular fibres,
and  strengthened  by oblique  and cuneiform bands, and is at-
 tached on each side to the ridge which separates the anterior
concave from the posterior or convex  surface of each phalanx ;
by this means the  tendon is confined  in the mesial line of the
finger.  All these sheaths are lined by a smooth synovial mem-
brane. 
OF  THE  LIGAMENTS.
123
                       CHAP. IX.


       LIGAMENTS OF THE  LOWER EXTREMITY.

                ILIO-FEMORAL LIGAMENTS.

  The hip joint has great freedom  of motion, and requires
powerful  ligaments;  it  is  therefore furnished with a synovial
membrane, a capsular ligament, an interarticular ligament, and
a cotyloid ligament.
                   COTYLOID LIGAMENT.

  This is a fibro-cartilaginous substance, attached to the whole
circumference of the acetabulum, except at its internal and in-
ferior part, where the bony part also of the margin is deficient;
it projects a  considerable  distance beyond the bone, so  as to
deepen the cavity very much.
  There is another strong band of fibres situated  at the lower
and internal  part of the acetabulum, where  the  last-described
ligament is  deficient: it  is  attached to the pubis, where this
bone forms the  sinus over the obturator ligament, and into the
ischium or inferior margin of the notch of the acetabulum:  this
ligament is  superficial  to  the  former,  and between   both  an
oblique fissure is left for the passage of vessels to and from the
cavity of the joint. 
124
FIBROUS SYSTEM
                   CAPSULAR LIGAMENT.

  The capsular ligament, o, embraces the whole articulation
of the  hip.   Excepting the capsular  ligament of the knee, it
                           surpasses  all  similar ligaments  in
                           strength, extent,  and capacity:  it
                           is attached at a  considerable dis-
                           tance from the margin of the cav-
                           ity, particularly  in front,  where  it
                           extends as far as  d, the inferior
                           spine of the  ilium ;  inferiorly it is
                           inserted into the  femur, incloses
                           the  neck of that  bone,  and de-
                           scends  as far as  c, the line which
                           lies between  the  two trochanters.
                           The synovial membrane  does not
                           descend so  low   as the external
                           capsule,  but is  reflected on all
 sides towards the head of the bone ; in this course it is bound
 by folds, and immediately behind  the head  of the femur it is
 confined by circular bands.   There is a fasciculus of fibres, o,
 taking an  oblique  course over the capsule towards the lesser
 trochanter, sometimes called the accessory ligament: it adds
 strength to this part of the capsule.
 
OF THE LIGAMENTS.
125
INTERAPTICULAR  LIGAMENT.
Ligamentum teres.
  The interarticular ligament
is a strong triangular fascicu-
lus  of fibres, perfectly con-
cealed within the cavity of the
acetabulum;  in  the  figure
there  is a section of the head
and neck of the femur, b, and
os innominatum, e, e, to show
the  attachments of this liga-
ment, c, to  the bottom of the
acetabulum and  to the head
of the femur.
LIGAMENTS OF THE KNEE JOINT.
CAPSULAR LIGAMENT.
  This ligament or membrane
is of a great extent, since the
knee joint is the largest of the
whole body ;  it is  attached
at b, h, d, to the  whole cir-
cumference  of the  condyles
of the femur ; anteriorly to e,
the  patella ; inferiorly to the
tibia,  and  to  the semilunar
cartilages.   Above  the hol-
low for the reception  of the
patella it lines /  the tendon
-a
 
126
FIBROUS  SYSTEM
of the extensor  muscles : it adheres also to the articular sur-
face of the patella in such a manner that this  bone  seems to
form part of the capsule of the joint; lastly, it is reflected over
the articular surface of i, the tibia, and  ligaments within  the
joints.  It is very loose  on  either side, but  tense posteriorly,
where it is closely connected with the  flexor tendons  and pos-
terior crucial ligaments.   These connexions, as  well  as the la-
teral ligament, serve to confine this membrane in its  situation,
and preserve it, in the motions of the joint, from being compress-
ed between the bones.
   This capsule of the knee, which in  itself is very  fine and
weak, receives considerable strength from additional fibres, term-
ed accessory ligaments.   These appear like duplicatures of the
capsule at the sides of the patella ; they are  also  called liga-
mentum alare, majus et minus.   There is a fold of the capsular
membrane of  the same character as those just described, but in-
closing a little fat, for which reason some  anatomists have given
it the name of adipose or mucous ligament;  it is situated very
near the external condyle, and in front of the anterior  crucial
ligament;  it retains  the synovial  substance in its proper place
in the  actions of the joint.  Another accessory  fasciculus of
fibres covers the capsular membrane posteriorly, called the pos-
terior ligament of Winslow. 
OF  THE  LIGAMENTS.
127
                   LATERAL LIGAMENTS.

  The lateral ligaments, as the  name  implies,  are  situated at
the sides of the joint, and adhere to the capsular ligament.
              EXTERNAL LATERAL LIGAMENT.

  The external lateral ligament, Fig. 103, a, is a thick round
chord, attached to a tubercle on the upper part of b, the exter-
nal condyle of the femur ; it is adherent to the semilunar carti-
lage on that side, and is inserted into c, the fibula, a little below
its head.
INTERNAL  LATERAL  LIGAMENT.
  The  internal lateral ligai ent,
a, is attached superiorly to the in-
ternal con yle, infer orJy to the
til ia, the  fibres passing obliquely
forwards till they have reached the
head of the bone, b, c, d,  the liga-
ment of the patella.
Fig. 104.
        b
 
128
FIBROUS  SYSTEM
                   CRUCIAL LIGAMENTS.

                                            Fig. 105.


  The crucial  ligaments, e, d, are
exposed in this figure by  throwing
down the patella, and removing the
adipose substance ;  they  are very
strong fibrous  cords, crossing each
other : hence their name.
              ANTERIOR CRUCIAL LIGAMENT.

  The anterior crucial ligament, d, is extended from the de-
pression between the two condyles of the femur to the spine in
the middle of the articular surface of the head of the tibia.


             POSTERIOR  CRUCIAL LIGAMENT.

  The posterior crucial ligament, e, is also extended from the
depression above named, to a groove behind the spine on the
tibia.  In Fig. 106, a, the crucial ligaments areseparated from
the femur, to show their direction and insertion  into the head
of the tibia.
   The ligaments of the patella, Fig. 103, /, g, is merely a con-
tinuation of the tendon of the  extensor muscles of the leg, in
the substance of which, e, the patella seems to be  formed in
a similar manner to  the sesamoid bones.   In Fig. 105, the
 
OF THE  LIGAMENTS.
129
patella is represented turned down over the head of the tibia; h,
 a synovial bursa  opened ; this is a remarkable bag, extremely
loose, and plentifully supplied with synovia.
INTERARTICULAR  OR SEMILUNAR CARTILAGES.
                  Fig. 105, b,f, Fig. 106, b, c.

  These  are  two  fibro-cartilages, placed  between   the  con-
dyles of the femur and the superior extremity  of  the tibia;
                             they are crescent  shaped, flexi-
                             ble and elastic; each of these
                             cartilages is broad in the middle,
                             and narrow at their extremities;
                             the outer convex  edge is thick,
                             the inner  concave  edge  thin,
                         c   thus rendering the cavities  for
                             the  condyles   of the femur
deeper, and adapting the tibia  more accurately  to that bone.
The extremities of these cartilages are fixed by ligaments to the
spine  in  the  centre of the articular surface of the  tibia; the
anterior  extremities  are joined to each  other by a  transverse
ligament;  the outer edges  adhere  to the capsular  and the other
ligaments, so as to  allow a little play or slight motion upon the
tibia, which by favoring the general motion of the  joint, has
been compared to the friction wheels of machinery.
LIGAMENTS BETWEEN THE TIBIA  AND  FIBULA.
  The tibia and fibula are united at their extremities by capsu-
lar and other ligaments, and in the  middle by an intervening
fibrous membrane.
  vol. i.                 18 
130
FIRBOUS  SYSTEM
                   CAPSULAR  LIGAMENT.

   The capsular ligament of the upper end of the fibula is con-
 tinuous  with the periosteum; some irregular fibres have been
 called anterior and posterior ligaments.  This  articulation is
 moreover  secured  by  the  external  lateral  ligaments of the
 knee, and by the tendon  of the  biceps flexor cruris,  part of
 which passes from the fibula to the tibia.

                 INTEROSSEOUS  LIGAMENT.

   The interosseous ligament of the leg resembles that which is
 between the radius  and ulna; it  is a thin  aponeurotic mem-
 brane, composed of oblique fibres extended from the outer edge
 of the tibia to the  inner edge of the fibula.   This  membrane
 presents several apertures for blood vessels.


  LIGAMENTS OF  THE LOWER END  OF  THE  TIBIA AND FI-
                           BULA.

   These ligaments  are anterior and posterior,  which  may be
 divided into superior and inferior,  according to their situations.
   The  superior ligaments are attached to the fibula and tibia,
 where these two  bones are in contact:  the  anterior having a
 triangular form, the  fibres being the shortest.
   The  inferior  ligaments  have  the same  direction as the
 superior;  they are not so  broad, but  are thicker  and  longer;
 they both extend from the extreme point of the tibia to the
 lowest part of the external malleolus.   These  four ligaments
 connect the tibia  and fibula so closely to  one  another, that they
 appear as one firm piece, whose base is  supported by two pro-
jections called malleoli, between which  the  astragalus  and os
 calcis, and of course the  whole foot, are firmly secured. 
OF THE  LIGAMENTS.
131
            LIGAMENTS OF  THE  ANKLE JOINT.

  Strong ligaments pass from the  malleoli  to the bones of
the  tarsus; there  is also a capsular membrane for the whole
articulation


     LIGAMENTS BETWEEN  THE FIBULA AND  TARSUS.

  The ligaments between the fibula  and  tarsus are three in
number;  the anterior passing from  the  point  of the external
malleolus forwards to the upper part of the astragalus.  The
middle is a strong fasciculus of fibres, which descends perpen-
dicularly  from the lowest point of the fibula to the side of the
os calcis.   The posterior is concealed by  the tendo Achillis :
it passes from the external malleolus  horizontally inwards, to
the back  part of the astragalus.
LIGAMENTS BETWEEN THE TIBIA AND TARSUS.

         DELTOID OR TIBIO-TARSAL LIGAMENT.


                         This ligament,  b,  is an  as-
                       semblage   of fibres   extending
                       from  the  internal malleolus  to
                       the  astragalus;  inferiorly,   its
                       fibres  diverge, and are attached
                       to the  os calcis, and by c, to the
                       os naviculare.
Fig. 107.
 
132
FIBROUS  SYSTEM
                    CAPSULAR  LIGAMENT.

  The capsular ligament, a, a,  is situated  within the former
ligaments; it covers the opposed surface of the bones which
enter into the articulation, and is  very loose: the  synovial
membrane which lines it contains a great quantity of synovia.
               LIGAMENTS OF  THE TARSUS.

  The seven bones of the  tarsus have  a very limited motion
between one another, or only such a degree of motion as gives
pliancy and elasticity in walking, running,  etc.   They  are
united in  a manner peculiarly strong, and well adapted to sup-
port the weight of the trunk in standing, or in the different mo-
tions of the body.   See Fig. 107. 
OF THE  LIGAMENTS.
133
LIGAMENTS BETWEEN THE OS  CALCIS  AND  ASTRAGALUS.
Fig. 108.
the adjacent part of the os calcis.
   There is, 1st, a  capsular
membrane, b,  c, connected
to the edges of the articular
surfaces of the two bones ;
it is closely covered by the
lateral ligaments of the an-
kle, and by  the  sheaths of
the tendons ;  2d, an interos-
seous ligament, formed of a
thick fasciculus of fibres, at-
tached  by one  part  to the
groove which separates the
two surfaces  of the astraga-
lus, and by the other to that
which  is between the  sur-
faces of the  os calcis ; 3d,
a  posterior  ligament,  com-
posed of parallel fibres,a, in-
serted into the posterior part
of the  astragalus and  into
LIGAMENTS BETWEEN THE ASTRAGALUS AND OS NAVICULARE.
  This articulation  has considerable motion ; for the  convex
head of the astragalus is received into the cavity of the navicu-
lar bone,  in  which it  is secured by a capsular and  accessory
ligaments. 
134
FIBROUS  SYSTEM
  LIGAMENTS BETWEEN  THE OS CALCIS AND NAVICULARE.

   We find two ligaments passing from  one of these bones to
the  other;  they are also connected  by a fibro-cartilaginous
trochlea, or inferior ligament, supporting the side of the head
of the astragalus, and affording a passage for the tendon of the
tibialis  posticus muscle ;  below this  ligament there are  two
external ligaments,  which  proceed from the anterior  internal
part of the os calcis to the external inferior part of the os navi-
culare.
 LIGAMENTS BETWEEN THE  OS CALCIS  AND OS CUBOIDES.

   There is, 1st, a superior ligament,  extending from the an-
terior part of the os calcis to the superior part of the os cuboi-
des ; 2d, an inferior ligament, composed of  a  superficial and
deep-seated fasciculus of fibres, passing from one  bone to the
other, and partly to the extremities of the third and fourth meta-
tarsal bones ; 3d, a capsular or synovial membrane, covering the
articular surfaces, and the two preceding ligaments.
LIGAMENTS  BETWEEN THE NAVICULAR AND  CUBOID BONES.

  These bones are connected  by a dorsal ligament, I,  com-
posed of transverse fibres, extending from the navicular to the
cuboid bone ;  and by a plantar ligament, extending obliquely
from the inferior part of one bone to the neighboring part  of the
other. 
OF THE  LIGAMENTS.
135
  LIGAMENTS  BETWEEN THE  NAVICULAR  AND  CUNEIFORM
                          BONES.

  The three surfaces of the os naviculare are  articulated with
those of the three cuneiform bones, 1st, by three dorsal ligaments,
g,i, k; 2d, by three plantar ligaments, similar to the  prece-
ding, extending from the inferior part of the  os naviculare to the
inferior surfaces of the three cuneiform bones ; 3d, by a syn'ovial
membrane, folded on the articular surfaces, and on  the plantar
and dorsal ligaments.

      LIGAMENTS BETWEEN  THE CUNEIFORM BONES.

  The cuneiform bones are maintained in apposition  by syno-
vial membranes ;  and by three superior ligaments, e, / k, ex-
tending transversely over their superior surfaces ; and by inferior
ligaments, similar to the preceding, but less distinct.

     LIGAMENTS BETWEEN THE  CUBOID  AND  EXTERNAL
                    CUNEIFORM BONES.

  The cuboid and external cuneiform bones are united together
by strong  ligamentous fasciculi, h, which pass from the edge of
one bone to that of the other.   The superior are termed dorsal,
the inferior plantar ligaments.

   LIGAMENTS  OF THE TARSUS  WITH THE METATARSUS.

  The tarsal and metatarsal bones are articulated together in a
similar manner to the carpus  and metacarpus ;  i.  e.  there  are,
1st,  capsular membranes;  2d, dorsal, m; 3d,  transverse liga-
ments, I, each of the metatarsal bones receiving one  from the
tarsal bone with which it is connected ; 4th, plantar ligaments : 
136
FIBROUS  SYSTEM
these are equal in number to the preceding, and disposed nearly
in the same manner.


LIGAMENTS OF  THE METATARSAL BONES WITH EACH OTHER.

   All the bones of the metatarsus, except the first, are articu-
lated together at their posterior extremities by  small  cartilagi-
nous  surfaces, covered by prolongations of the  capsular mem-
branes of the preceding articulations, and maintained, 1st, by
dorsal and plantar ligaments ; these extend transversely in each
region from the  second to the third, and from the  third to the
fourth, and from the fourth to the fifth metatarsal  bones; 2d,
by interosseous fibres, found between the inarticulated points
of the-posterior extremities of these bones ; and 3d, by transverse
metatarsal ligaments, o, situated at  the  anterior extremities of
the metatarsal bones, and are in all respects similar to those I
have  described as belonging  to the heads  of the four last meta-
carpal bones.


LIGAMENTS OF  THE METATARSUS WITH THE  PHALANGES OF
                         THE TOES.

   The posterior extremities of the first phalanges are connected
to the metatarsal bones at n by capsular  and lateral ligaments.


      LIGAMENTS OF  THE  PHALANGES OF  THE TOES.

   These ligaments are similar to those of the fingers.
   The tendons of the foot also are provided  with  nearly  the
same  sheaths and ligaments as  those  in the hand, for  the  pur-
pose of confining them in their situation, and directing them in
their proper course.   The tendons which  pass in front and at
each side of the  ankle joint, are firmly secured by ligaments and 
OF THE  LIGAMENTS
137
tendinous  sheaths, which are attached to the  adjacent bones;
anteriorly, the extensor tendons  are bound down by a strong
annular ligament, whose fibres take a circular direction.
  The plantar aponeurosis is composed of strong ligamentous
fibres, extending from the os calcis as far as  the first  phalanges
of the toes, where it is lost in the tendinous sheaths.  Each of
the flexor tendons is confined by a strong ligamentous sheath,
which is continued along the phalanges, in the  same manner as
in the hand ;  each sheath is strengthened by circular bands at
different situations.   On  the sides of  each  articulation of the
phalanges with the metatarsus, a  fascia is sent off from the ex-
tensor tendon ; it  is composed  of ghstening fibres, which  run
toward the sole of the foot, and unite with the plantar aponeu-
rosis ; these fasciae are  of important service in  retaining  the
extensor tendons in their situation.
VOL. I.
19 
ART.  IV.
                        CHAP. I.


                    MUSCULAR SYSTEM.

  The organs, which we distinguish by the term  muscles, are
composed of that substance which is commonly known by
the name of  flesh ; those,  therefore, who have  not seen the
muscles of the human body, may form a very good idea of them
by an examination of the flesh of quadrupeds.
  The muscles are instruments or active agents in  producing
the various movements of our body ; by  their means we are
endued with the power of moving from place to place, and of
performing every  manual  exercise or bodily exertion.  Not
only are they the  prime  moving powers  in  locomotion, but
speech, singing, and  the acts of chewing,  swallowing,  etc.,
are performed by them ;  indeed,  by means of these organs the
blood is  circulated, the stomach  and intestines urge on  their
contents, and the different conduits of the  glands  propel  their
fluids.
  The most characteristic property of muscles is contractility;
in whatever position our limbs may repose, it must be muscular
contraction to  produce their action.  Muscular contractility is
displayed in the amputation of a limb ; for immediately as soon
as the muscles  are divided, the two ends contract in opposite 
MUSCULAR  SYSTEM.
139
directions, leaving between them  a space proportionate to the
retraction of the muscles, which is more or less, according to
the length of the muscular fibres.
   This  contractility of  muscles  constitutes muscular action,
and consists in  drawing  the more movable towards the most
fixed point to which it is connected.  Every movable point in
the animal frame is constantly  situated between two muscular
powers opposed to  each other; between  those of flexion and
extension, of elevation and depression, of adduction and abduc-
tion, etc.; this  opposition  is a condition essential to motion ;
for in whatever direction  the  limb is to be moved, the movable
point must necessarily be in the opposite direction ;  the act of
flexion requires that it should be first extended, and vice versa.
But when flexors and extensors are both  in a  state of action,
they counterbalance each other;  there is  a rigid state of  the
muscles, and the limb is fixed.   The effect of every muscle
that contracts, is not only to act upon the bone into which it is
implanted, but  also  on the  opposite  muscle, and this consti-
tutes the phenomena of antagonist muscles ; the  muscles  are
so situated that  the one  class cannot be extended without the
other contracting, and reciprocally.   I shall be pardoned  if I
give the familiar but clear explanation  of Paley in reference
to antagonist muscles ; — " Every muscle is provided with an
adversary.   They act  like two sawyers in a pit, by an oppo-
site pull;  the  nature of  the muscular fibre  being  what it is,
the purposes  of the animal  could be answered  by no other.
And not only the capacity for motion, but the aspect and sym-
metry of the  body, is  preserved by the  muscles  being thus
marshalled according to this  order; e. g. the mouth  is holden
in the middle of the face, and its angles kept in a state of exact
correspondency, by several muscles drawn against  and balan-
cing each other.  In hemiplegia, when the muscles on one side 
140
MUSCULAR  SYSTEM.
of the face are weakened, the muscles on the other side draw
the mouth awry."
   The muscles on contracting, become evidently harder ; they
increase  in thickness and decrease in  length, but their volume
remains nearly the same ; what is lost in length is compensated
in thickness.  Prevost and Dumas describe their fibres, in a
state of repose,  as straight lines ; but, when acting, all at once
bending themselves in a waved  direction, and presenting in an
instant a great number of angular and regularly opposed undu-
lations, thus, ^^=s^ ;  if the cause which led to the  con-
traction ceases, the right lines of the fibres are restored with the
same rapidity as the waved lines were produced.
   This contractility, on which depend  all the  phenomena of
animal motion, and  which also promotes  many of the exterior
and  interior  functions, is  exclusively seated  in  the muscular
system.   It possesses the faculty of moving under the influence
of the brain, whether that influence be determined by the will
or by other causes.   If the brain of a man is compressed, the
faculty of contracting the muscle ceases.  The intensity of
muscular contraction, that is, the  degree of power with which
the extremities of the fibres approximate, is in proportion to the
excitement of the brain ; it is generally  regulated by the will,
according to certain limits, which  are different in different indi-
viduals.   When the  organization of the muscles is strongly
fibrous, and they are  of a deep red color, such muscles, with an
equal power of the will, produce  much more powerful efforts
than muscles whose  fibres are  fine, pale and  smooth.  The
cerebral  influence and the structure  of the muscular tissue,
therefore, are the two elements on which depends the intensity
of muscular contraction.
   Irritability of muscles, called by  Haller the vis insita, is
the  latent power inherent in  the muscular fibres, producing
that tremulous motion which  is often  felt in various parts of 
MUSCULAR  SYSTEM.
141
the body, without any evident cause,  and  independent of the
will.  It is to be distinguished from muscular contractility by
being more permanent, and by occurring on the application of
chemical or mechanical stimuli.   A muscle may  be separated
from the limb, or the heart removed from the body, and for
some time afterwards, on  pricking it with a needle or passing the
electric shock through it, there will be seen convulsive twitch-
ings of its fibres.  The irritability of a muscle is  present  after
death ;  and, though doubtless a phenomenon worthy of study, is
not to be confounded with the muscular contraction I have just
described.


                  FORM  OF THE  MUSCLES.

   The  muscles, like the bones,  with reference to their forms,
may be divided into long, wide,  and short muscles.


                    THE LONG  MUSCLES.

   These muscles are generally placed on the limbs, to the con-
 formation of which they very much contribute.  Separated from
 the skin by a strong membrane called aponeurosis, and from the
 bone by periosteum, they are contained in a fibrous envelope,
 which strictly maintains them  in their respective situations and
 in which they are disposed in layers more or less numerous.   In
 proportion, however, as they are  deeper seated they also become
 shorter; they are separated by cellular layers, loose in  parts in
 which extensive motions are performed, and tight wherever the
 motion  is more confined.   The  long muscles are in  some in-
 stances a single bundle of fibres, in others they result from an
 assemblage of many ; scarcely any of the fibres run the whole
 length of the fleshy mass ;  in most of the  muscles they are dis-
 posed in  an  oblique  direction,  between  two  aponeuroses, or 
142
MUSCULAR SYSTEM.
between a tendon and an  aponeurosis.   Some muscles  have
tendinous intersections, which are placed at different distances
in the course of the fibres.


                    THE WIDE MUSCLES.

   These  muscles are generally situated on the parietes of the
cavities, especially on those of the chest and  abdomen, whose
parietes are chiefly  formed by them ;  they protect the inter-
nal organs, aid their functions, and move the body or limbs ac-
cording as the one or the other is the fixed point.   They  have
always short tendons.
   The wide muscles are not  very thick;  the greatest  part of
them representing muscular membranes, sometimes disposed in
layers, as on the abdomen, at other times applied over the long
muscles, as on the back.   When the wide muscles are attached
to, or are inserted into one of the great cavities, they preserve
in all the parts nearly the same width ;  but if from a cavity a mus-
cle extends to a long bone, the fibres  concentrate by degrees,
grow narrower and thicker, and the muscle terminates in a ten-
don, and thus contracts into a narrow compass the fibres which
are largely disseminated.  The pectoral and great dorsal mus-
cles are instances  of this form and disposition.


                   THE SHORT MUSCLES.

   These muscles are commonly met with in  parts where  con-
siderable power on the one  hand, and a limited extent of motion
on the other, is required, as in  the movements of the jaw, the
hip, the thumb, and the foot; and most of them have a square
or triangular shape.  Numerous muscles attached to the spine,
as, the interspinales, recti, etc., display the form I am here de-
scribing.   They are the most powerful of all the muscles, and 
MUSCULAR  SYSTEM.
143
are placed where great force is required, as at  the articulation
of the jaw, in the vertebral column, he.   Though the division
of the muscles into long, wide, and  short, is  similar to  that  of
the bones, and is generally applicable, yet it is liable to a mul-
tiplicity of modifications : since nature varies according to the
functions which  the  organs  are intended  to perform.
   There are further distinctive characters of muscles, viz., they
are simple when the fibres have a parallel direction, as the sar-
torius or the quadratus lumborum ;  if they proceed from an ex-
tended surface, and converge to a  small tendon,  they are termed
radiated, as the temporal muscle.  When the tendon occupies
the middle of the muscle, and the fibres  are placed obliquely  to
the tendon like a feather, the  muscle is named penniform,  as
the rectus femoris ; where the muscular fibres are placed on one
side of the tendon, it is called half-penniform,  as  the peroneus
jongus.  In  the  compound  muscles there is a single mass  of
muscular fibres and several tendons, like the flexors of the fin-
gers, or there are several muscular and tendinous portions, as  in
the sacro-lumbalis, etc.   Sometimes the  bundles  of the fibres
and tendons  are  variously and often intricately woven, as in the
lingual muscles.
     VOLUNTARY,  INVOLUNTARY, AND  MIXED  MUSCLES.

  The division of the muscles into voluntary and involuntary is
sufficiently accurate to convey a distinct idea of the two classes
of exciting causes.   In ordinary circumstances those under the
influence of  the will must  be voluntary muscles, such  as the
muscles of locomotion.   But there are other muscles over which
the will has no dominion :  the vital  organs, the heart, stomach,
and  intestines,  afford examples of this description, and are
brought forward by writers on natural theology  as marks of the
Divine wisdom;  for were the action of these organs within the 
144
MUSCULAR  SYSTEM.
control of the will, and the vital functions left  to  man's gov-
ernment, I need not say they would be subject  to  a thousand
interruptions;  these organs, therefore, are furnished with invol-
untary muscles.  There is another class of muscles, which are
termed mixed, as the diaphragm and other muscles of respira-
tion, the orbicularis oculi, etc.; of the  action of these  muscles
we are not sensible, unless the attention of the  mind be direct-
ed to them ;  yet we  have the power of increasing or suspend-
ing their action for a certain length of time.


                   TEXTURE OF  MUSCLES.

  The muscular or fleshy fibres are soft, red, downy, linear, and
possess a small degree of elasticity ; they retain  little tenacity
in the  dead body, and are easily torn  asunder, but  during life
they resist very great force  without breaking.   A muscle is
composed of a number of muscular fasciculi, which are formed
of fibres still  smaller ;  these  result from fibres of less volume;
at least, by progressive division, we arrive at a fibre no  longer
practically divisible, but which were our means of division more
perfect, possibly  might be reduced to such a degree of tenuity
as to elude even the microscope.  However,  the last of these
filaments which can be perceived is the muscular fibre.   Num-
berless researches have  been made to determine  with certainty
the volume of this fibre ;  I  need not mention the result of these
researches :  the correctness cannot be relied on,  and the inves-
tigation could add nothing to our notions  respecting muscular
motion.
  Every muscular fibre runs its extent without ramifying; it is
merely in juxta-position with the adjoining ones.   The intimate
nature  of this fibre, upon which so much has been written, is still
unknown to us.  Prohaska* found the muscular fibre ^Vs Part
* Operum minorum pars i. p. 198. 
MUSCULAR  SYSTEM.
145
of an inch in diameter, while Mr. Bauer*  estimates it at only
g-^ViT'  The latter describes  the fibres as moniliform, that is,
consisting of globules  lineally and  closely arranged, like  the
beads of  a  necklace.    Sir  E. Home is  inclined to consider
these globules to be  the remains of the globules of  the blood
from which they have originated, an opinion which the facts of
the case by no means warrant;  and all that has been affirmed
respecting  the continuation  of the  muscular  fibre  with  the
nervous or vascular organs, is supported by no positive  proofs,
and is  unworthy of claiming a moment's attention.  " To ar-
rive at correct conclusions, we  must study nature where  she
comes  within the cognizance of our senses ."f
             CELLULAR TISSUE OF  MUSCLES.

  The fibres of muscles are united by this substance ; it is one
of the most important elements of the animal system, consisting
of very minute, soft, white filaments, crossing  each other in a
multitude of different directions, and leaving between them cer-
tain  interstices  which serve  for the  reception of fat.   The
muscles  are abundantly  supplied with this  cellular web ;  it
forms a very considerable layer round every muscle ; it is most
generally loose, or  filled with fat; sometimes  it is tighter, and
actually  spread in  the  form  of a membrane, and then the
dissection becomes  difficult  for the  young student.   Besides
affording this general covering to the muscles, it extends into
the substance of these organs themselves, and  largely contri-
butes to  their structure ;  each fasciculus is provided with a con-
tinuation of sheaths of cellular  tissue, and not only surrounds
and  binds the muscles together, but  also unites each of their

     * Phil. Trans. 1818, p. 175.               t Bichat.
  vol. i.             20 
146
MUSCULAR  SYSTEM.
fibres with those adjoining.   These  coverings accommodate
the motions of the fibres, which they separate from each other,
either by the fat which they contain, or by  the serum  of the
cellulae.
   The quantity of intermuscular cellular tissue varies very con-
siderably ; sometimes it  is  so  abundant among the muscles as
to  divide  them into separate portions, and consequently has
confused anatomists in the division of these organs.*
                BLOOD-VESSELS  OF MUSCLES.

   With the exception  of certain  viscera, as the  lungs, liver,
spleen, etc., few organs, in proportion to their size, receive more
blood than the muscles ; the blood being  essentially necessary
to keep up excitement,  and  by this  fluid the human muscles
are colored.   The  arteries   are  exceedingly apparent; they
penetrate their substance from all points of their surface.  The
principal branches creep at first between the largest fasciculi of
fibres; then they  divide and  subdivide into an  almost infinite
number of ramifications, which, reduced to capillary tubes, sup-
ply the secondary skeins, twine  among the most minute fibres,
and deposite the nutritive substance of the muscle.
   The veins of muscles constantly attend the arteries, but sur-
pass them, as they do in all other parts of the body, in number
and magnitude.
   The absorbent  vessels may be  traced, but not without diffi-
culty.   They are most readily injected in the muscles of  the
face, the tongue, and the diaphragm.

  * In consequence of these cellular  intersections, some  authors have di-
vided the deltoid muscle into three  distinct muscles. As another instance,  I
may mention also the pectoralis major,  which is thus divided into a clavicular
and sternal portion. 
MUSCULAR  SYSTEM.
147
                   NERVES OF MUSCLES.

  The muscles are liberally endowed with nerves; indeed, ex-
cepting the skin and organs of sense, no part, of the body is so
abundantly supplied with  them.    Each branch, on  reaching
the fleshy fibres, first divides,  then subdivides in the interstices,
until  it  entirely disappears.   Dr. Monro thought that  each
individual fibre had  its corresponding nervous filament; and the
observation of Bichat may induce one to  believe it, namely,
that on the principal nervous branch being irritated, every fibre
of the muscle comes into play.


                   TENDONS  OF MUSCLES.

   The tendons are  a part of the  muscle : they are a kind of
fibrous cord, conducting the motions of the muscle to the bone,
particularly where  there is not room for the insertion of the
muscular fibres which are necessary for the motion of the joints ;
they frequently concentrate the whole power  of  a very large
muscle  on  a small bony surface ;  indeed, without such a medi-
um of  attachment, the  articulations would be encumbered in
their  actions.  The tendons are composed of small white fibres,
closely united to each other, having a beautiful  shining silvery
appearance;  they  differ from the ligaments chiefly in this par-
ticular,  that one of their extremities is attached to the muscle.
   Tendons possess very little elasticity  or sensibility;  they
have  few  blood-vessels, in  fact none  are observed  in  their
ordinary state; nor have nerves or lymphatics been traced into
them.
   Some muscles form  a complete  circle,  and have no tendi-
nous  structure, and are termed sphincters. 
148
MUSCULAR  SYSTEM.
   Usually the tendons are at the extremities  of muscles, but
 sometimes are found in the middle, as in the digastric muscles,
 the diaphragm, omo-hyoideus, &c.


                         APONEUROSIS.

   Aponeuroses are  precisely similar to tendons;  frequently
 they seem to  result from the expansion  of a  tendon.  They
 may be divided into two  classes ; 1st, Aponeuroses of inser-
 tions,  those fibrous expansions which  receive  fleshy fibres, so
 as to afford the greatest advantage in multiplying prodigiously
 the  points of  insertion, without increasing the extent of bony
 surface, as the  tensor vaginae femoris ; others  collect the mus-
 cular power into  a  line of attachment, as in the oblique and
 transverse muscles  of  the abdomen.    2d, Enveloping apon-
 euroses ;  these are  found  around the  limbs where they main-
 tain  the  muscles  in  their  respective  situations,  so that  in
 great exertions, the muscles are  not  liable  to  displacement;
 their inner surfaces often send  fibrous partitions between the
 muscles which  extend  to the periosteum of  the neighboring
 bone;  and at  the  same time that they  retain the  muscular
 fibres in their  situation, give  points for their insertion.  Like
 the tendons, their  hue is of a resplendent white ; in a healthy
 state they  have little vascularity, and may be considered as
 destitute of sensibility.


           CHEMICAL COMPOSITION OF  MUSCLES.

  Owing to the difficulty of  separating  the  muscular fibres
from the fat, blood,  cellular membrane, etc., with which they
are very intimately blended, the  organic elements of the mus-
cular tissue are still involved in  obscurity;  but when freed 
MUSCULAR  SYSTEM.
149
as much as possible from those substances which adhere to them,
they consist of albumen, a great quantity of fibrin, and a prin-
ciple of a peculiar nature, colored, soluble in alcohol, giving to
broth its taste and smell, named osmazome.   There also occur
in these organs a coloring matter, carbonate, hydrochlorate, and
phosphate of soda, phosphate of lime, and oxide of iron.
                  SHEATHS OF TENDONS.

  In general these sheaths form a semi-cylindrical  canal, com-
pleted by the bone in the opposite part in such a manner that
the  tendon slides in a canal, which is partly bony and  partly
fibrous ;  this canal is lined with a synovial  membrane.  On
their external surfaces the fibrous sheaths correspond to the ad-
jacent parts with which they are united, and adhere to them by
loose cellular tissue.   All  the  sheaths  are  composed of  dense
and strong fibres ; indeed, stronger  than  might be supposed  to
be sufficient to restrain the efforts of the tendons that act upon
them; the tendons are thus kept down in their proper places,
and are prevented  from deviating from  their  destined  course.
Some of these sheaths, as those at the wrist and on the instep,
contain the united tendons of several  muscles: these bear the
name of annular ligaments;  the tendons of the hand and foot
having to pass a narrow space, it was indispensably necessary they
should be there maintained.  Other sheaths, as those of the fingers,
are  intended for a single tendon, or for two only.  Besides these
uses, the sheaths in some cases change the direction of the ten-
don, as we observe  in the trochlea of the eye,  and the  sheaths
of the tendons of the thumb and little finger. 
150
MUSCULAR  SYSTEM.
                  STRENGTH  OF MUSCLES.

  The natural strength of muscles  probably  depends on  the
number of  fibres which enter into their composition; but the
effect of habit  and exercise of the muscles in giving strength,
mobility,  and  dexterity,  is astonishing.    The  muscles grow
stronger in proportion as they are used, provided they are well
used, and not exhausted by violence or over exertion; but  the
same muscles in different individuals, though of the same length
and  thickness, and, as  far as we are able to examine composed
of the same number of fibres,  are by no  means uniform in  the
degree of power they are  capable of  exercising.   Under par-
ticular excitement the muscular  efforts  may  be carried to a
wonderful degree ; we know the strength of an enraged person,
of maniacs and of persons in convulsions ;  but such violent con-
tractions cannot be carried beyond a  certain time, after which
a painful feeling-of weariness takes place, which goes on increas-
ing until the muscle refuses to act:  by rest, however, the feel-
ing of fatigue subsides, and the muscles recover their wonted
energies.   If, however, the brain of a man be  compressed,  the
faculty of contracting the muscle ceases ; the nerve of a muscle
being cut, the  muscle loses all power of contracting, thus show-
ing that muscular action depends on the brain,  and that it is
generally regulated, to a certain  degree, by the will.*


  * " There are many muscles given to us which the common customs and
habits of life seldom render it necessary to exert, and which, in consequence,
grow stiff and immovable.  Tumblers and buffoons seem to be aware of this
fact;  and it is principally by the cultivation of these neglected  muscles that
they  are able to assume those outrageous postures and grimaces, and exhibit
those feats of agility, which so often  amuse and surprise us." — Dr. Good's
Book of Nature. 
MUSCULAR  SYSTEM.
151
                  ACTIONS OF  MUSCLES.

  Many muscles acting together, producing the same kind  of
motion, are called congeneres; those which act in the opposite
direction are termed antagonistes.   The first ordinarily arise
from the same fixed point or from the same region, the second
or antagonists from the opposite.
  The various movements produced by the contraction of mus-
cles are, adduction and abduction,  flexion and  extension, and
rotation, etc.  These various  motions are not usually effected
by  the action of one muscle alone,  but by the co-operation  of
several congeneres.
  The flexors are commonly stronger than the  extensors, and
it is for this reason, that when the  extremities are at rest, or in
in a state of freedom, or in paralysis, or during sleep, that they
are bent  or slightly flexed.  And the flexors are attached fur-
ther from the centre of motion than the extensors, and their di-
rection is less parallel to the bone; consequently  the angle is
more open, and the power more favorably applied.


             NOMENCLATURE OF THE MUSCLES.

    Th denomination of the muscles is derived from several con-
 siderations, as, viz., from their
    Size, as great, small, long, broad, thin ;
    Figure, as triangular, scalenus,  deltoid, orbicular, rhomboi-
 dal, etc.;
    Direction, as straight, oblique,  transverse ;
    Composition, as complexus, triceps, biceps,  semimembrano-
 sus, perforans, etc.  ;
    Attachment,  as  stylo-hyoideus, pterygoideus, sterno-cleido-
 mastoideus;                                   "
    Uses,  as flexors, adductors, rotators, etc. 
152         CLASSIFICATION  OF  MUSCLES.

  The inconvenience from such a multiplicity of names from
such different sources, has long been felt among anatomists, and
many nomenclatures have been suggested to remove it.  All the
synonyms of muscles may be found in Lizar's System of Anat-
omy.
            CLASSIFICATION OF THE MUSCLES.

  The muscles have been distributed into classes, according to
the different parts of the body  which they  occupy: each of
these parts has received the name of region.  The following
table presents a general view of the names and classification. 
TABLE OF  THE  MUSCLES.              153
                           CHAP. II.



                   TABLE OF THE MUSCLES.


  The total number of the muscles amounts to  527, of which

257 are pairs, and lie on either side  of  the  body.   There are

four single muscles situated on the middle  line, independent of

those muscles which perform the  internal vital functions.


                     MUSCLES OF THE HEAD.

  1. Cranial region.                 Occipito-frontalis.

                                 C Attollens auris.
  2, Auricular region.             < Attrahens auris.
                                 ( Retrahens auris.


                     MUSCLES OF THE FACE.


  1. Palpebral region.
2. Ocular region.
3. Nasal region.
4. Superior maxillary region.
5.  Inferior maxillary region.
  Orbicularis palpebrarum.
  Corrugator supercilii.
  Levator palpebral superioris.

 C Rectus superior.
 } Rectus inferior.
J Rectus internus.
 } Rectus externus.
 t Obliquus superior.
  Obliquus inferior.

  Pyramidalis nasi.
  Compressor nasi.
  Levator labii superioris, alaeque nasi.
  Depressor alas nasi.

 r Levator labii superioris.
 | Levator anguli oris.
«{ Zygomaticus major.
 | Zygomaticus minor.
 L Orbicularis oris.

 " Depressor anguli oris.
  Depressor labii superioris.
 i Depressor labii inferioris.
 j Buccinator.
  Levator menti.
 _ Masseter.
VOL. I.
21 
154             TABLE  OF  THE  MUSCLES.
6. Temporo-maxillary region.

7. Pterygo-maxillary region.



8. Lingual region.




9. Palatine region.
  Temporalis.

< Pterygoideus externus.
I Pterygoideus internus.

C Hyo-glossus.
) Genio-glossus.
j Stylo-glossus.
(_ Lingualis.

r Circumflexus palati.
} Levator palati.
J Levator uvulae.
j Palato-pharyngeus.
L Constrictor isthmi faucium.
MUSCLES  OF  THE NECK.
1.  Anterior cervical region.
2.  Superior hyoidean region.
3. Inferior hyoidean region.
4. Pharyngeal region.
5.  Deep cervical region.
6.  Lateral  cervical region.
C Platysma myoides.
I Sterno-cleido-mastoideus.

 f Digastricus.
J Stylo-hyoideus.
 J Mylo-hyoideus.
 L Genio-hyoideus.

 C Omo-hyoideus.
 ) Stjrno-hyoideus.
"} Sterno-thyroideus.
 L Thyro-hyoideus.

 f Constrictor pharyngis inferior.
 ) Constrictor pharyngis medius.
"j Constrictor pharyngis superior.
 (_ Stylo-pharyngeus.

C Rectus capitis anticus major.
< Rectus capitis anticus minor.
( Longus colli.

C Scalenus anticus.
< Scalenus posticus.
^ Rectus capitis lateralis.
MUSCLES  OF  THE TRUNK.
1. Anterior thoracic region.


2. Lateral thoracic region.


3. Intercostal region.


4. Diaphragmatic region.
C Pectoralis major.
< Pectoralis minor.
( Subclavius.

  Serratus magnus.

C Intercostales externi.
i Intercostales interni.
j Triangulares sterni.
L Levatores costarum.

  Diaphragma. 
TABLE  OF  THE  MUSCLES.              155
MUSCLES  OF THE  ABDOMEN.
1. Abdominal region.




2. Lumbar region.



3. Anal region.





4. Genital region.
 r Obliquus abdominis externus.
 j Obliquus abdominis internus.
<{ Transversalis abdominis.
 .' Rectus abdominis.
 L Pyramidalis.

 C Psoas magnus.
t Psoas parvus.
  Iliacus internus.
  Quadratus lumborum.
C Levator ani.
< Coccygeus
( Sphincter ani.

 £" 1st.  (In the male)  Cremaster ischio-
     cavernosus.
 j Bulbo-cavernosus.
•^ Transversus perinaei.
  2nd. (In the female.)  Ischio-caver-
     nosus.
  Constrictor vaginas.
MUSCLES OF  THE POSTERIOR PART OF  THE TRUNK.
1. Lumbo-dorsal region.
2. Dorso-cervlcal region.
3.  Posterior occipito-cervical
    region.
4. Vertebral region.
C Trapezius.
( Latissimus dorsi.

C Rhomboideus.
j Levator anguli scapula?.
I Serratus posticus superior.
«J Serratus posticus inferior.
I Splenius.
I Complexus.
[_ Trachelo-mastoideus.

C Rectus capitis posticus major.
i Rectus capitis posticus minor.
■{ Obliquus capitis superior.
| Obliquus capitis inferior.
v- Interspinalis cervicis.

r Longissimus dorsi.
| Sacro-lumbalis.
< Transversus colli.
j Multifidus spinae.
L Intertransversales colli  et lumborum. 
156              TABLE  OF  THE  MUSCLES.
MUSCLES  OF  THE SHOULDER.
1.  Posterior scapular region.


2. Anterior scapular region.
3. External scapular region.
C Supra-spinatus.
J Infra-spinatus.
j Teres minor.
L Teres major.

  Subscapularis.

   Deltoides.
MUSCLES  OF  THE ARM.
1. Anterior brachial region.

2.  Posterior Brachial Region.
Coraco-brachialis.
Biceps flexor cubiti.
Brachialis internus.

Triceps extensor cubiti.
MUSCLES  OF  THE  FORE-ARM.
1.  Anterior region of the fore-
    arm.
2.  Anterior deep region of the
    fore-arm.
3. Posterior superficial region
    of the fore-arm.
4. Posterior deep region of the
    fore-arm.
5. Radial region.
f Pronator teres.
J Flexor carpi radialis.
I Palmaris longus.
\ Flexor carpi ulnaris.
j Flexor digitorum sublimis vel perfo-
L   ratus.

f* Flexor digitorum profundus vel per-
)   forans.
) Flexor longus pollicis manus
 L Pronator quadratus.

f" Extensor digitorum communis.
J Extensor proprius minimi digiti.
| Extensor carpi ulnaris.
L Anconeus.

 f* Extensor ossis metacarpi pollicis.
) Extensor primi et  secundi internodii
 )   pollicis manus.
 L Indicator.

 C Supinator radii longus.
) Supinator radii brevis.
J Extensor carpi radialis longior.
 L Extensor carpi radialis brevior. 
TABLE  OF THE  MUSCLES.              157
MUSCLES OF THE HAND.
1. External palmar region.
2.  Internal palmar region.
 f Abductor brevis pollicis manus.
J Opponens  pollicis.
 | Flexor brevis pollicis manus.
 ^Adductor pollicis manus.

 C Palmaris brevis.
  Abductor  minimi digiti.
 j Flexor proprius minimi digiti.
 | Adductor  ossis  metacarpi minimi
    digiti.
 ^Lumbricales.
3.  Middle palmar region.  >  Interossei.   •<
1.  Abductor indicis.
2.  Adductor indicis.
3.  Abductor digiti medii.
4.  Adductor digiti medii.
5.  Abductor digiti annularis.
6.  Adductor digiti annularis.
7.  Abductor minimi digiti.
MUSCLES OF THE HAUNCH AND  THIGH.
1.  Region of the hip.




2.  Pelvi-trochantric region.




3.  Anterior femoral region.



4.  Internal femoral region.



5.  Posterior femoral region.
 f Gluteus maximus.
< Gluteus medius.
 (^ Gluteus minimus.

 f Pyriformis.
  Obturator  internus.
J Obturator externus.
 j Gemellus superior.
 I Gemellus inferior.
 ^Quadratus femoris.

  {Sartorius.
  Rectus femoris.
  Triceps extensor cruris.

  ' Pectineus.
  Gracilis.
< Adductor longus.
  Adductor brevis.
 ^ Adductor magnus.

  {Biceps femoris.
  Semitendinosus.
  Semimembranosus. 
158              TABLE  OF  THE  MUSCLES.
MUSCLES  OF THE LEG.
1.  Anterior region of the leg.


2.  Peroneal region.


                                  [
                                  I
3.  Posterior region of the leg.     <
  {Tibialis anticus.
  Peroneus tertius.
  Extensor longus digitorum pedis.
  Extensor proprius pollicis pedis.

( Peroneus longus.
i Peroneus brevis.

  Gastrocnemius externus.
  Gastrocnemius internus.
  Soleus.
  Plantaris.
  Popliteus.
 j Flexor longus digitorum pedis.
 j Tibialis posticus.
 (^ Flexor longus pollicis pedis.
MUSCLES  OF THE FOOT.
1.  Dorsal region.
2.  Plantar region.
C Extensor brevis digitorum pedis.
I Interossei externi.

 r Flexor brevis digitorum pedis.
  Abductor pollicis pedis.
  Abductor minimi digiti pedis.
  Flexor digitorum accessorius.
  Lumbricales pedis.
  Flexor brevis pollicis pedis.
  Adductor pollicis pedis.
  Flexor brevis minimi digiti pedis.
  Transversus pedis.
  Interossei interni. 
MUSCULAR  SYSTEM  OF THE  HEAD.       159
MUSCLES   OF  THE  HEAD.


          CRANIAL REGION.


      OCCIP1TO-FRONTALIS.

             Fig. 109.
  This is the only muscle which properly belongs to the scalp ;
it consists of two distinct parts, an  anterior and a posterior,
which are united by  an aponeurosis or tendinous membrane.
The posterior portion, a, has an aponeurotic and fleshy attach-
ment to the transverse ridge of the occipital bone ;  it forms,  b,
the  cranial aponeurosis, a broad fibrous expansion which covers
the  whole upper part of the cranium :  the anterior portion, seen
in Fig. Ill, a, is attached to c, the circular muscle of the eye-
lid,  and to the skin ; and by  b, to the inner angle  of the fron-
tal bone, and the os nasi.  The outer  surface of  this muscle
is covered by the integuments, the inner rests on the cranium.
  The anterior portion of this muscle raises the brow,  wrinkles 
160
MUSCULAR  SYSTEM
 the forehead, and brings forward  the integuments of the head;
 the posterior draws back the skin to its original situation.  The
 direction of  the  muscular fibres and the aponeurosis are also
 seen, Fig. 112, a, b.*

                      AURICULAR REGION.

                     ATTOLLENS  AURIS.

   Fig. 112.   The attollens auris, c,  is of a triangular figure,
 situated on the temple above  the ear; superiorly it is attached
 to the cranial aponeurosis, and  inferiorly to the cartilage of the
 ear.  The outer surface of this muscle is covered by the  skin,
 the inner covers the temporal aponeurosis.
   The action of this muscle raises the ear.


                     ATTRAHENS  AURIS.

   The attrahens auris, d, is situated before the ear, and has the
 same form as the  preceding ;  anteriorly it is attached  to the
 border of the cranial aponeurosis, and posteriorly to  the  carti-
 lage or anterior helix of the ear.
   This muscle draws the ear forward and upward.  The outer
 surface of this muscle is covered by the skin ;  the inner is sit-
 uated upon the temporal muscle and temporal artery.


                    RETRAHENS  AURIS.

   This muscle, e,  is situated behind the ear, and is extended
 from the mastoid  process of the temporal bone to the back  of
the ear.  It frequently consists of two small bundles of fibres,
and is then described as two muscles.

  * This is sometimes divided by anatomists into two muscles, the occipital
and frontal muscles. 
OF THE  HEAD.
161
  This muscle is covered by the integuments, and is separated
from the temporal bone by cellular tissue.  The action of this
muscle carries the ear backwards.*

                  MUSCLES OF  THE  FACE.

                      PALPEBRAL REGION.

                ORBICULARIS  PALPEBRARUM.

                    Fig. Ill, c, Fig. 112,/.

  The fleshy fibres of this muscle surround the orbit of the eye,
and  form  part of the eyelids ;  superiorly it is attached to the
frontal bone, and inferiorly to the superior maxillary bone, where
it has a tendinous point of insertion into the nasal process.
  The anterior surface of this muscle is covered by the integ-
uments ;  the posterior is applied upon the corrugator supercilii,
the fibro-cartilage of the upper eyelid, the malar bone, the mus-
cles  of the superior maxillary region, the ligament and fibro-car-
tilage of the lower eyelid, the ascending process of the superior
maxillary  bone, and  the lachrymal sack.
  This muscle shuts the eye, by bringing down the upper eye-
lid and raising the lower, the fibres contracting  towards the in-
ner angle  ; it also depresses the eyebrow  at the same  time  it
raises the  cheek.

                 CORRUGATOR SUPERCILII.

                           Fig. 111.

  This  muscle, p,  is  placed  on the  arch of the orbit, in the
thickness  of the eyebrow ; it is attached on the one part to the
superciliary ridge, and  on the other to  the occipito-frontalis and
orbicularis muscles.

  * The other muscles of the ear will be described with the organ of hearing.
  VOL.  I.                   22 
162
MUSCULAR  SYSTEM
  The anterior surface of this muscle is covered by  the orbic-
ularis palpebrarum, the occipito-frontalis, and the pyramidalis
nasi muscles; the posterior is in contact with the frontal bone,
the superciliary artery, and the frontal branch of the ophthal-
mic nerve.
  This muscle draws down the brow in the expressions of an-
ger and the malevolent passions.
LEVATOR PALPEBR.E SUPERIORIS.

             Fig. 110.
  This muscle, a, is situated in the superior part of the orbit,
and is fixed to the bottom of it; it is  then spread out into a
broad tendon, which is attached to  the cartilage of the upper
eyelid, as is seen also in Fig. Ill, n.
  The superior  surface of this muscle is connected with  the
orbit and frontal  branch of  the ophthalmic  nerve;  and more 
OF THE  HEAD.
163
anteriorly it is separated from  the orbicularis palpebrarum by
the palpebral ligament j the inferior is connected with the rec-
tus superior and membrana conjunctiva.
   The action of this muscle raises the upper eyelid.
                     OCULAR^REGION.

                    RECTUS  SUPERIOR.

                          Fig. 110.

  This muscle, b, is situated in the orbit above the eye, under
the levator palpebrae ; it is broad  and thin, tendinous at its ex-
tremities, and fleshy in the rest of its extent.   Posteriorly it is
attached to the optic foramen, and anteriorly to the membrana
sclerotica.
  The superior surface  of this muscle is covered by the prece-
ding ; the inferior is placed upon the optic nerve, the ophthal-
mic artery, and the nasal branch of the ophthalmic nerve, in
front upon the eye itself.
  The action of this muscle raises the eye.


                    RECTUS INFERIOR.

  The figure and structure of d, the rectus inferior,  is like  the
preceding ; posteriorly it is attached to the inferior part of the
optic foramen, and anteriorly to the  sclerotic membrane.
  The inferior surface  of this muscle is  separated from  the
floor of the orbit by adipose tissue ; the superior is in connexion
with the optic nerve, a branch of the third pair of nerves, and
the  eye.
  This muscle  is the antagonist  of the  rectus  superior, and
draws the eye downwards. 
164
MUSCULAR  SYSTEM
                     RECTUS INTERNUS.

   This muscle, c, c,  is similar to the two described;  it is situ-
ated on the inner side of the eye, and is attached posteriorly to
the margin of the optic foramen ; anteriorly, to the inner side of
the eye.  In this figure the central  part is removed to show k,
the optic nerve, but its attachments are preserved.
   This muscle draws the eye towards the nose.
                     RECTUS EXTERNUS.

   The rectus externus is similar in its figure and attachments to
 the other recti, but is situated on the outer side of the eye.  In
 this figure the muscle is supposed to be removed.
   The outer surface of this  muscle  is in apposition with the
 orbit and lachrymal gland ;  the inner with the optic nerve, the
 sixth pair, and the lenticular ganglion.
   The office of this muscle is to carry the  eye outward.


                    OBLIQUUS SUPERIOR.

   This muscle, e, is situated  at the internal and superior part of
 the orbit; posteriorly it is attached to the optic foramen, passes
 forward horizontally to  the  internal  orbitar process, where it
 forms a thin round tendon, which passes through/, a cartilagi-
 nous ring ;* runs obliquely downwards and backwards, and is
 inferiorly attached at g, by a radiated tendon,  to  the globe of
 the eye.  On the inside of the pulley or ring is a synovial cap-
sule, which is reflected over the tendon.

      * At least this loop forms a ring with the superciliary notch. 
OF THE  HEAD.
165
  This  muscle is situated between  the orbit  and  the  optic
nerve, the superior and internal recti muscles, and the globe of
the eye.
  The office of this muscle  is to roll  the eye, and to turn the
pupil downwards  and outwards.
                   OBLIQUUS  INFERIOR.

  This muscle  is situated  at the anterior  part  of the orbit.
Anteriorly it is attached at i, the inner edge of the orbitar pro-
cess of the superior maxillary bone, near  its union with the os
unguis ; it  is directed backwards and  outwards, under d, the
rectus inferior, and is attached posteriorly  by A, a thin tendon,
to the sclerotic  membrane.
  The inferior surface of this  muscle is placed on the floor of
the orbit; the  superior  corresponds  with the ball of the eye,
and with the rectus inferior.
  By means  of the inferior oblique muscle the eye  is  turned
upwards and  inwards. 
166
MUSCULAR  SYSTEM
NASAL REGION.
PYRAMIDALIS  NASI.

      Fig. 111.
   This muscle,  b,  is  confounded with the  occipito-frontalis;
its figure is thin and triangular ;  it is attached by its summit to
the last-named muscle, covers the nasal bones, and is  fixed by
its base to the compressor nasi.   This muscle is sometimes re-
garded as merely a portion  of  the frontal muscle; the upper
part is certainly  intermixed with  it, but the lower part is very
distinct.
  The anterior surface is connected with the skin ; the poste-
rior with the corrugator supercilii, the os frontis, and  the pro-
per bones  of the nose.
  This muscle assists in bringing down the integuments of the
forehead, and raising the skin of the nose. 
OF THE  HEAD.
167
COMPRESSOR NASI.

      Fig. 112.
  This muscle, Fig.  Ill, o, Fig. 112, A, is  attached on the
outer side of the cartilage of the nose to the  adjacent part of
the bridge of the nose, where it meets its fellow.
  The anterior surface is covered by  the skin, the posterior
lies upon the superior maxillary bone and upon the lateral car-
tilage of the nose.
  This muscle compresses the nostrils ;  it sometimes acts with
the pyramidal  and frontal muscles, to which it  is connected,
and then it  raises the nostril.
        LEVATOR  LABII SUPERIORIS  ALiEQUE  NASI.

  This muscle, Fig. 112, i, is attached  by a small tendon to
the nasal process of the superior maxillary bone, close by the 
168
MUSCULAR  SYSTEM
tendon of the orbicular muscle of the eyelids ;  as it approaches
the nose it is spread out into two portions, one of which is in-
serted into the ala or cartilage of the nostril, the other into the
upp3r lip.
  The anterior surface  is placed beneath the skin, and at its
upper part it is concealed by the orbicularis palpebrarum.  The
posterior  is  connected with the preceding muscle, the nasal
process of the  superior maxillary bone, the border of the leva-
tor labii superioris, and the depressor nasi.
  This muscle raises the ala of the nostril and the upper lip.
                   DEPRESSOR AI.M NASI.

   This muscle, Fig.  113, e, is a small fleshy fasciculus, placed
beneath the ala or wing of the nose.  Superiorly it is attached
to it;  inferiorly to the superior  maxillary  bone  immediately
above the upper incisor teeth.
   The fibres of this muscle are covered by those of the levator
labii superioris  alaeque  nasi, and  by the mucous  membrane of
the mouth, and are applied  to the superior  maxillary bone.
   The contraction  of this muscle depresses the ala of the nose.
               SUPERIOR  MAXILLARY  REGION.

                LEVATOR  LABII SUPERIORIS.

   This muscle, Fig. 112,  k, is situated  in the  middle of the
face ; superiorly it is attached to the lower part of the orbit,
inferiorly to the upper lip  ; it  contracts as  it descends, and its
fibres are  confounded  with the circular muscle  of the lips,
between the  nose and  angle of  the  mouth.   At the upper
part, this muscle is covered by the orbicularis palpebrarum, and 
OF THE  HEAD.
169
at the lower  part by the skin.  The posterior surface is in
connexion with the levator anguli oris, from which it  is sepa-
rated by the infra-orbitar vessels and nerves.
                  LEVATOR ANGULI  ORIS.

  This  muscle, Fig. 112, I, is situated near the middle of the
face;  superiorly it is attached  to the canine fossa ;  inferiorly to
the angle of the mouth.
  The anterior surface is  connected, as we see in the figure,
with other muscles of the face ;  the posterior surface with the
canine fossa, the  mucous membrane  of the mouth,  and  the
buccinator muscle.
  This muscle raises the angle of the mouth.


                   ZYGOMATICUS MAJOR.

  This is a long and slender muscle, Fig. Ill,/, Fig. 112, m,
situated on the side of the face, and passing downwards and in-
wards ; superiorly it is attached to the upper part of the cheek
bone ; inferiorly to the corner of the mouth.


                   ZYGOMATICUS  MINOR.

  This muscle, Fig. Ill, e, Fig.  112, n, is not  found in all
subjects.   It  is situated on the  inner side  of the preceding
muscle between k, the  elevator of the upper  lip, and m, the
great zygomatic muscle. It passes in the same direction as the
last-mentioned muscle, and has nearly  the same attachments.
  The anterior surfaces of the  zygomatic muscles are gene-
rally covered by a great quantity of fat as well as skin ; the
 vol.  i.                23 
170
MUSCULAR  SYSTEM
posterior surfaces are placed on the malar bone and the buc-
cinator muscle;  their connexion with the other muscles  of
the face is obvious in the figure.
   The zygomatic  muscles raise the angle of the mouth, as in
laughing, etc.

                     ORBICULARIS ORIS.

   The form of this muscle, Fig.  Ill, t, Fig. 112, t,i s ellipti-
cal ;  its fibres are found  in the substance of the lips, and are
completely interlaced and  confounded with those of the other
muscles which terminate  near the angle of the mouth.
   The skin adheres  firmly  to  the  anterior surface of this
muscle ; the posterior surface is lined by the mucous mem-
brane of the mouth, and  its free edge is invested with the red
membrane of the lips.  The connexion with the other muscles
of the face is intricate.
   This muscle is an antagonist to the other muscles of the lips;
it is a true sphincter  muscle, contracting the  aperture of the
mouth ; its action is evident in playing the flute, in sucking, in
masticating, &c.

                  INFERIOR  MAXILLARY REGION.

                 DEPRESSOR  ANGULI ORIS.

  This muscle, Fig. Ill,  k, Fig. 112, o, is of a  triangular
form,  and situated at the lower part of the face; superiorly it
is attached  to  the  lower jaw; inferiorly  to the angle of the
mouth, where the fibres are confounded with those of the leva-
tor anguli oris.
  The outer surface adheres  to the skin  and  the  platysma
myoides ; the inner is connected with the  buccinator and the
depressor labii inferior is.
  This muscle  depresses the angle of the mouth, and its action
expresses grief. 
OF THE  HEAD.
171
              DEPRESSOR  LABII INFERIORIS.

  This muscle, Fig. 111, m, Fig. 112, p, is thin,  and nearly
quadrilateral;  its situation in the face is obvious in the figures
referred to.  Inferiorly it is  attached to the  lower jaw ; superi-
orly  to the  lower lip, where its fibres are confounded with the
orbicularis.
  The anterior surface is connected with the skin  and part of
the preceding muscle.   The posterior  surface  is connected
with  the lower jaw, the mental  vessels  and  nerves,  the levator
menti, and the labial muscles.
  The use of this muscle is  to pull the lip downwards.
                       BUCCINATOR.

  This muscle, Fig. 112, s, is situated in the cheek ; superi-
orly  it is attached to the sockets of the  molar teeth of the
upper jaw; behind, it is connected with the constrictor muscle
of the pharynx, and in front with the angle  of the mouth.
The middle fibres  are horizontal, the superior  and  inferior  a
little converging to the angle of the lips.   It is perforated in the
middle by the duct of the parotid gland.
  The outer  surface is covered  by a thick layer of fat,  the
zygomaticus major, the platysma myoides, the depressor anguli
oris, the  skin, and labial artery and vein.   The inner is lined
by the mucous membrane of the mouth.
  This muscle is  seen remarkably dilated  in blowing the horn
or trumpet; its use is to force the air out of the mouth by con-
tracting its cavity, to draw the angle of the mouth backwards,
and in mastication to press  the food within  the line of the
teeth. 
172
MUSCULAR  SYSTEM
                     LEVATOR MENTI.

  This muscle, Fig. 112, r, is placed on the chin ; superiorly
it is  attached to the depression on the side  of the symphysis of
the jaw, under  the alveoli of the incisor teeth.  The fibres
diverge downwards, and are inserted into the skin of the chin.
  Anteriorly it is covered by the skin ; posteriorly by the mu-
cous membranes of the mouth.
  This muscle raises  the chin.
                        MASSETER.

  This muscle, Fig. Ill, A, Fig.  112, v,is composed of apon-
eurotic and fleshy fibres, situated on the side of the face ; it is
very thick,  and attached superiorly to the two anterior thirds
of the inferior part of the zygomatic arch, to its internal surface,
and to the aponeurosis of the temporal muscle; inferiorly to
the angle of the lower jaw, to its  external  surface, and to the
inferior  border  of the ramus of the  same.   The  masseter is
sometimes described as  two distinct portions which decussate
one another ; the anterior portion   running  backwards, is fixed
into  the side of the lower jaw as far as the angle; the poste-
rior portion  passing forwards, is united to the coronoid process.
  On the outer side is found the  parotid  gland  and  its duct,
the platysma myoides, the  facial nerve, the  transverse  facial
artery, etc.   The inner surface is  placed on  the ramus of the
mferior maxilla, the tendons of the temporal and the buccinator
muscles.
  This muscle raises the lower jaw, and acts powerfully during
mastication. 
OF  THE  HEAD.
173
TEMPORO-MAXILLARY REGION.


      TEMPORALIS.

         Fig. 113.
  The situation  and direction of the fibres of this  muscle  are
shown  in the annexed figure:  a portion of  c, the  zygoma, is
removed to show the whole of  the  muscle.  It occupies  the
whole temporal cavity, and is covered with  a strong^aponeuro-
sis, while another is placed in the midst of the fleshy fibres, di-
viding it into two planes, terminating inferiorly in a strong ten-
don.   It is attached superiorly  to the temporal fossa, and to a,
a, b, the semicircular line bounding it; inferiorly at d, the coro-
noid  process of the inferior maxilla.
  The outer surface of the temporal muscle is covered by  the
epicranial aponeurosis, the superior and anterior auricular mus-
cles,  and a portion  of the orbicularis palpebrarum and masse-
ter muscles ;  the superficial temporal vessels and nerves also
ramify  over it.   The inner surface  is situated upon the tern- 
174
MUSCULAR  SYSTEM
poral fossa and the internal maxillary artery.   The pterygoi-
deus externus, and buccinator muscles, are separated from it by
a considerable quantity of fat.
   The office of this muscle, as well as the preceding, is to draw
the lower jaw upwards.  In carnivorous animals the temporalis
is the strongest muscle in the whole body.


                  PTERYGO-MAXILLARY  REGION.


                 PTERYGOIDEUS EXTERNUS.

                          Fig. 114.
   This muscle is situated in the zygomatic fossa ;  it is attached
by one portion at b, c, to the external surface of the pterygoid
process, and by the other to the zygomato-temporal surface of
the sphenoid bone ; from thence the muscle is directed outwards
and backwards, and is inserted into  a, the anterior part of the
neck of the condyle of the lower jaw, and into the fore part of the
circumference of the interarticular cartilage. 
OF  THE  HEAD.
175
  The outer surface is in contact  with the  temporal muscle,
and frequently with the internal maxillary artery.  The inner
surface corresponds with the pterygoideus internus, the inferior
maxillary nerve, and the middle meningeal artery.  The upper
surface touches the zygomatic  fossa and the temporal and mas-
seteric nerves.
  This muscle brings forward and to the opposite side the con-
dyle of the jaw  and the interarticular cartilage ; when the pair
of muscles act together, the jaw is  drawn directly forwards.
                 PTERYGOIDEUS INTERNUS.

  This muscle, d, is placed at the inner and posterior part of the
branch of the  inferior maxillary bone.   It is attached superiorly
by tendinous and fleshy fibres to the inner plate of the pterygoid
process of the sphenoid bone, and  to the pterygoid process of the
os palati, filling all the space between the two plates: inferiorly
it is attached  by tendinous and fleshy fibres to the inside of the
angle of the lower jaw.
  The inner surface  is connected with the circumflexus palati,
the constrictor pharyngis superior, and the  sub-maxillary gland.
The  outer surface lies upon  the inner  part of the branch of the
lower jaw, much in the same manner as the masseter does upon
the outer part.
  When the pair  of  muscles act together, they  bring the jaw
horizontally forwards ;  when they act singly, the jaw is moved
obliquely to the opposite side.   The pterygoid muscles move
the jaw from side to side, and perform  the motion  of grinding
with  the teeth. 
176
MUSCULAR  SYSTEM
LINGUAL REGION.

 HYO-GLOSSUS.


   Fig. 115.
  This muscle, d, is situated at the front and upper part of the
neck ; it  is thin, flat, and quadrilateral.  Inferiorly,  its fibres
are attached to the os  hyoides ; superiorly, to  the side  of the
tongue, and mix with  a, e, the fibres of the stylo-glossus.
  The outer surface is covered by the stylo-glossus, the mylo-
hyoideus,  the genio-hyoideus and  digastricus, the hypo-glossal
nerve, and the sub-maxillary gland.  The inner surface is con-
nected with the constrictor pharyngis medius, the genio-glossus,
the lingual artery and  the glosso-pharyngeal  nerve.
  The hyo-glossus draws the tongue inwards and downwards.
                      GENIO-GLOSSUS.

  This muscle, i, k, is  situated  between the  tongue and I,
the lower  jaw;  its fibres  are  radiated,  extending from  the 
OF THE HEAD.
177
mental process to the inferior surface of the  tongue and the  os
hyoides.
  The external surface of the genio-glossus is connected with
the sublingual gland,  and the stylo-glossus,  hyo-glossus, lingu-
alis, and mylo-hyoideus muscles ;  the internal surface is in con-
tact with that of the opposite side.
  According to the  direction of its fibres, so it moves  the
tongue : those which go to the point draw it backwards ; those
which pass backwards thrust the tongue  out of the mouth ; and
the central f bres have the power of rendering the upper surface
of the tongue concave.
                      STYLO-GLOSSUS.

  This muscle takes an oblique direction from above where it is
attached, at a, to the styloid process of the temporal bone, and
to/, the stylo-maxillary ligament;  the muscular fibres are finally
lost at e, in the substance of the tongue.
  The outer surfac  is covered by the digastricus, the lingual
nerve, the sub-maxillary gland, and the  mucous  membrane of
the mouth :  the inner surface covers the constrictor pharyngis
superior, the hyo-glossus, and the  lingualis.
  The stylo-glossus moves the tongue sideways and backwards
when it acts alone; but when it  contracts  at the same time
with the corresponding muscle,  the  tongue is carried upwards
and backwards.
                        LINGUALIS.

  The fibres of this muscle run from the root to the tip of the
tongue, and are intermixed at its lateral parts with the muscles
just mentioned.
  vol. i.  '            24 
178
MUSCULAR SYSTEM
  The upper surface is confounded with the fleshy texture of
the tongue ; the lower surface is covered by the mucous mem-
brane of the mouth.
  This muscle contracts the tongue and depresses its point.
     PALATINE REGION.

CIRCUMFLEXUS PALATI.

        Fig. 116.
  This muscle is placed in the substance of the velum  of the
palate.  Superiorly it is attached to the wing of the  sphenoid 
OF  THE  HEAD.
179
bone and to the Eustachian tube ;  its tendon, / passes round
the hook of the internal  plate of the pterygoid process of that
bone, and spreads into g, a tendon at the semilunar edge of the
os palati and  velum palati.
   The external surface is covered by the pterygoideus internus;
the inner surface is in apposition with the levator palati and
constrictor pharyngis  superior,  the  mucous membrane  of the
pharynx and of the velum palati.
   This muscle stretches the palate horizontally.


                     LEVATOR PALATI.

   The shape and direction of this muscle,  b, b, is  apparent in
the figure.  Superiorly it is attached  at m, the petrous portion
of the temporal bone; the inferior fibres are inserted into a, the
pendulous part of the palate, its fibres being confused with  the
other muscles in  that situation.
   The outer surface is connected with the  circumflexus palati,
the palato-pharyngeus, and the constrictor  pharyngis superior;
the inner  is lined by  the mucous membrane of the pharynx and
of the velum palati.
   This muscle draws the  curtain of the palate upwards and
backwards in the time of  swallowing, and thus prevents  the
food or drink from passing into the nose.


                     LEVATOR UVULJE.

   This muscle, a, occupies the substance of the uvula,  or that
small fleshy  substance  hanging in  the  middle of the  palate.
The uvula muscle is one of the four instances of a single mus-
cle ; it is attached to the palate bones, and runs down the whole
length of the uvula,  adhering to the  tendons of g, the circum-
flex  muscle. 
180
MUSCULAR  SYSTEM
  It is connected anteriorly with the levator palati, and is cov-
ered posteriorly by the membrane of the velum palati.
  This muscle raises the uvula.
                   PALATO-PHARYNGEUS.

  This muscle is placed in the substance of the velum palati
and that of the pharynx ;  superiorly it is attached, at c, to the
arch of the palate ; inferiorly, at d, to the thyroid cartilage, and
the bag of the pharynx.
  The posterior surface of this muscle  is covered by the mu-
cous membrane of the velum palati, and the constrictores pha-
ryngis  ; the  anterior surface is connected with the aponeurosis
of the  circumflexus palati and  the  mucous membrane  of the
pharynx.
   This muscle draws  the uvula downwards  and backwards,
shuts the passage of  the posterior nostrils, and assists in swal-
lowing.
              CONSTRICTOR ISTHMI  FAUCIUM.

  This is a small fleshy fasciculus, A, attached to the curtain
of the palate and to the base of the tongue.
  The action of this muscle lowers the velum palati, and assists
b raising the tongue. 
OF THE  NECK.
181
CHAP. III.
MUSCLES  OF  THE  NECK.


     ANTERIOR CERYICAL REGION.


       PLATYSMA MYOIDES.


              Fig. 117.
  This is an extremely thin layer of fleshy fibres, spread  over
the other muscles, and attached to the cellular membrane of the
neck; it requires some skill in dissection to display this muscle,
for as it is merely a web of muscular fibres, it is frequently re-
moved  with the integuments unnoticed.   Superiorly  it extends
to a, the face, where its fibres are lost in  the  cellular tissue of 
182
MUSCULAR  SYSTEM
the cheek, and inferiorly to  b ; its fibres cover a portion  of c,
the pectoral, and of d, the deltoid muscles.
   The outer surface of this muscle is covered by the skin;
the inner is placed  over the deltoides, pectoralis  major and
sterno-cleido-mastoideus muscles,  the  clavicle, the muscles of
the hyoidean and maxillary regions, and the sub-maxillary and
parotid glands.
   This muscle draws the  skin of the cheek  downwards, and
when the mouth is shut, brings the  skin under the lower jaw
upwards.

                STERNO-CLEIDO-MASTOIDEUS.

                           Fig. 118.
  This muscle is situated at the side of the neck.   Superiorly
it is attached, at a, to the mastoid process of the temporal bone,
and to a part of the occipital bone ; inferiorly, at b, to the sum-
mit of the sternum, and at c, to the internal third of the supe-
rior border of the clavicle.
  The outer surface is covered by the platysma  myoides, ex-
cepting at its upper extremity, which lies under  the skin and 
OF  THE  NECK.
183
parotid gland; between it and the preceding muscle the exter-
nal jugular vein  and some nervous filaments of  the  cervical
plexus are situated.   The inner surface is connected to the ar-
ticulation of the sternum with  the clavicle, the sterno-thyroi-
deus,  sterno-hyoideus, and omo-hyoideus muscles, the  internal
jugular vein, the carotid artery, the pneumo-gastric  nerve,  the
scaleni, the levator scapulae, the splenius and digastric  muscles.
                      DIGASTRICUS.

  Tliis muscle is so called from having two bellies, g, g, one
of which is attached to the mastoid groove of the temporal bone,
and becomes tendinous in the  middle, traversing a  perforation
in h, the stylo-hyoideus muscle ; the other is inserted into the
inner part  of the chin,  Fig.  119,  A.   The central tendon is
braced down by aponeurotic  fibres to d, the os hyoides.
  The outer surface is covered by  the lesser complexus, sple-
nius, and sterno-cleido-mastoideus  muscles ; the submaxillary
gland is lodged in the angle formed by the tendon.   The inner
surface is placed upon the stylo-hyoideus, the stylo-glossus, and
the stylo-pharyngeus muscles, the external and internal  carotid
arteries, the internal jugular  vein, the hypo-glossal  nerve,  and
the hyo-glossus and mylo-hyoideus muscles.
  When the mouth is shut the action  of this muscle raises the
os hyoides, and the pharynx  at  the time of  deglutition ; when
these parts are fixed it opens the mouth.
                     STYLO-HYOIDEUS.

  The form  of this muscle, Fig. 118, A, is  long and  slender,
having a tendinous attachment superiorly to the styloid process, 
184               MUSCULAR SYSTEM
and inferiorly tod,  the os hyoides.   Its perfcra on to ""d- t
the tendon of the digastricus has been  mentioned in the prece-
ding description of that muscle, and is  also represented in Fig.
115.
   The digastric muscle  is extended across the  outer surface;
the inner is  connected with  the external carotid, labial, and
lingual  arteries, the internal jugu'ar  vein,  the stylo-glossus,
stylo-pharyngeus,  and hyo-glossus muscles, and the hypo-glos-
sal nerve.

                      MYLO-HYOIDEUS.

   This  is a broad, thin, triangular muscle, Fig. 115, i ; supe-
riorly it is attached to nearly  the whole extent of the inside of
the lower jaw, between the molar teeth and the chin ; inferiorly
the fibres converge,  and are inserted into the os hyoides.  This
muscle  unites with its fellow  in a  middle line, which  extends
from the os hyoides  to the chin.
   The outer surface is covered by the digastricus, the platysma
myoides, and the submaxillary  gland  ; the inner is placed  in
contact with the genio-hyoideus, genio-glossus, and hyo-glos-
sus, the sub-lingual  gland, the prolongation o. this g'and, and
the lingual nerve.
   This muscle raises the os hyoides, or depresses the jaw.

                      GENIO-HYOIDEUS.

   This muscle, Fig. 115, k,  Fig. 119, i, is  placed above  the
preceding; its  figure is  thin  and narrow.  Anteriorly it is  at-
tached to the mental process of the lower jaw ;  posteriorly to
the surface of the body of the os hyoides.
   The  anterior surface is covered  by the mylo-hyoideus ; the
posterior is in  contact with the genio-glossus and hyo-glossus;
the inner edge meets that of the opposite side.
   The  action  of this muscle  raises  the os hyoides, carrying it
forward, or it depresses the lower jaw. 
OF THE  NECK.
185
INFERIOR HYOID  REGION.


   OMO-HYOIDEUS.

       Fig. 119.
   This muscle, c, c, and in the preceding figure, e, e, is situa-
ted at the side of the neck ;  it is  very long, thin, and narrow.
Superiorly it is attached to the hyoid  bone, descends  obliquely
across the neck,  and forms  a tendon in its  centre, where it
passes behind the sterno-cleido-mastoideus, and becoming fleshy
again, is inserted  into the root of the coracoid process and semi-
lunar notch of the scapula.
   The outer surface is  covered by the trapezius, the  platysma
myoides, and the  sterno-cleido-mastoideus ; we see in the figure
the clavicle lying across it.   The inner surface corresponds to
the scaleni muscles, the anterior branches of the inferior cervi-
cal nerves,  the primitive carctid artery, the  internal jugular
   vol.  i.                    25 
186
MUSCULAR  SYSTEM
vein, the superior thyroidean  vessels, the sterno-hyoideus  and
sterno-thyroideus muscles.
   This muscle depresses the  hyoid bone,  drawing it a little
backwards.
                     STERNO-HYOIDEUS.

   This is a long, thin muscle, Fig. 119, b, presenting gene-
rally towards its middle an aponeurotic intersection.  Superiorly
it is attached to the body of the hyoid bone ; inferiorly to the
superior part of the sternum, the. clavicle, and sometimes to the
first rib.
   The clavicle passes across the anterior surface of this mus-
cle, and is covered by  the  sterno-cleido-mastoideus, the omo-
hyoideus, the platysma-myoides, and by the common  integu-
ments.   The posterior surfa :e is in apposition with the sterno-
thyroideus,  crico-thyroideus, and thyro-hyoideus muscles, the
thyro-hyoid membrane, the thyroid gland, and the superior thy-
roid vessels.
   This muscle depresses the larynx, and furnishes a fixed point
for the depressors of the jaw.
                    STERNO-THYROIDEUS.

  This muscle, d, is placed  behind the former, and its form is
like it; superiorly it is attached  to the thyroid cartilage;  infe-
riorly to the upper and posterior part  of the sternum, opposite
the cartilage of the fi t rib.  It frequ  ntly presents  at its lower
part an oblique or transverse aponeurotic intersection.
  The anterior surface is covered by  the sterno-hyoideus, ster-
no-cleido-mastoideus, and omo-hyoideus muscles.   The pos-
terior surface covers the subclavian and internal jugular veins, 
OF  THE  NECK.                  187
the primitive carotid artery, the trachea, the thyroid gland, the
crico-thyroid muscle, and  a part of the constrictor pharyngis
inferior.
   This muscle draws the larynx downwards.
                     THYRO-HYOIDEUS.

  This is a small oblong muscle, e, attached superiorly to  »the
hyoid bone, and inferiorly to the thyroid cartilage.
  The anterior surface of this muscle is covered by the sterno-
hyoideus, the omo-hyoideus,  and  the platysma myoides;  the
posterior lies upon the thyroid  cartilage,  and the thyro-hyoid
membrane.
  This muscle brings the  larynx and hyoid bone towards each
other. 
188
MUSCULAR  SYSTEM
         PHARYNGEAL REGION.


CONSTRICTOR PHARYNGIS  INFERIOR.


              Fig. 120.
   This is the largest muscle, c, of the  pharynx.   It is  broad
and membranous ; anteriorly it is attached to A, the thyroid and
cricoid cartilages, and to i, the upper rings of the trachea ; pos-
teriorly it  is united to  its fellow, in a vertical  tendinous line.
The direction of the fibres is expressed in the figure. 
OF THE  NECK.
189
  The exterior  surface is  covered by the sterno-thyroideus,
the thyroid gland, and the primitive carotid artery. The poste-
rior  surface  is connected with the rectus capitis anticus major
and  longus colli muscles, and with the anterior vertebral liga-
ment by cellular tissue.  The  interior  surface  is covered by
the constrictor medius, palato-pharyngeus, and  the stylo-pha-
ryngeus muscles, the mucous membrane of the pharynx, and
the thyroid and cricoid cartilages.
  This muscle contracts that part of the pharynx which it
covers.

             CONSTRICTOR  PHARYNGIS MEDIUS.

  This muscle, b, is of a triangular shape situated at the middle
part  of the pharynx.   It is attached anteriorly to the greater
and lesser horn of g,  the hyoid bone, and to the stylo-hyoidean
ligaments ; posteriorly to its fellow, in a tendinous line  at the
back of the pharynx, and superiorly it is  fixed  to the  basilar
process of the occipital bone.   Observe the direction of its
fibres in the figure.
  This muscle is connected on its outer surface  with the hyo-
glossus muscle and  the lingual artery,  and  with the  inferior
constrictor below ;  in the rest of its extent it is connected with
the muscles of the deep  cervical region  and the anterior verte-
bral  ligament.  The inner surface is  covered by the mucous
membrane of k, the pharynx, the stylo-pharyngeus, palato-
pharyngeus, and the  superior constrictor muscles.
  This muscle compresses that part of the pharynx which it
invests.

           CONSTRICTOR PHARYNGIS SUPERIOR.

  Like the  other constrictors,  this  muscle, a, is broad and
thin; its figure  is nearly quadrilateral.  It is partly  covered 
190
MUSCULAR  SYSTEM
by the middle constrictor, and its connexions are most exten-
sive.   Superiorly, it is attached to  the occipital bone before
the  large  foramen;  lower down, to  the  pterygoid process
of the sphenoid bone, to the upper and under jaw near the last
molar teeth, and  to  k, the buccinator muscle.   Some fibres
also  are fixed to the root of the tongue, and palate. Posteriorly,
like the two preceding, its fibres  are united in a line to the cor-
responding muscle.
  The outer surface is connected with the preceding muscle,
the stylo-glossus, the stylo-pharyngeus, the internal carotid arte-
ry, the internal jugular vein, the  pneumo-gastric, hypo-glossal
and spinal nerves.  These different parts occupy a triangular
space, which is found between the constrictor pharyngis  supe-
rior and the pterygoideus internus.   The inner surface is con-
nected with the palato-pharyngeus and the levator palati, and
is lined by the mucous membrane of the pharynx.
  This muscle compresses the pharynx at the upper part; the
constrictors act in succession,  and contract that portion of the
alimentary canal when it is filled  with food, and force  it down
wards into the oesophagus. 
OF  THE  NECK.
191
STYLO-PHARYNGEUS.
  This
thyroid
    FiS-121-            This muscle is situated at the
                     side and back part of the pharynx;
                     it is  attached superiorly to a, the
                     styloid process, and inferiorly it is
                     expanded on the  pharynx  and
                     back  part  of the  thyroid carti-
                     lage.
                       The outer  surface  is  covered
                     by the stylo-hyoideus, constrictor
                     medius, and external carotid arte-
                     ry ;   the  inner is connected with
                     the  internal  carotid  artery,  the
                     internal  jugular  vein,  the  mu-
                     cous  membrane  of  the pharynx,
                     and  the  superior constrictor  and
                     palato-pharyngeus muscles.
muscle raises the pharynx, and also draws upwards the
cartilage.
DEEP CERVICAL  REGION.
             RECTUS  CAPITIS ANTICUS  MAJOR.

   This muscle, Fig. 122, a, is placed on  the anterior and late-
ral part of the cervical column ; superiorly it is attached to the
basilary process of the occipital bone ; inferiorly by small  ten-
dons to the anterior tubercle of the transverse processes of the
third, fourth,  fifth, and sixth cervical  vertebras.   It is a  little
drawn aside in the figure to show the muscle  to  be next de-
scribed.
  The anterior surface corresponds  to the carotid artery, the 
192
MUSCULAR SYSTEM
internal  jugular vein, the  pneumo-gastric  nerve, the  superior
cervical  ganglion,  and  the pharynx;   the posterior surface
covers the longus  colli, the rectus capitis anticus minor, the
articulation of the atlas with the  occiput, the  articulation also
of the axis or dentatus with the  atlas, and  also the transverse
processes of the cervical  vertebrae.
   If this muscle acts in conjunction with  that  of the  opposite
side, it bends  the  head forward ;  and  laterally, if it acts by
itself.
RECTUS  CAPITIS ANTICUS  MINOR.

              Fig. 122.
   This is a small and  thin muscle,  e, situated close to the up-
permost vertebra ;  it is tendinous  at its insertions, aponeurotic
at its anterior surface, fleshy  in the rest of its extent.  Superi-
orly it  is  attached  to  the occipital bone  near  the condyle;
inferiorly to the atlas, or first vertebra. 
OF THE NECK.
193
  It is connected  anteriorly with the preceding muscle; pos-
teriorly with the articulation of the atlas and occiput.
  This muscle assists the preceding in  supporting or  bending
the head.
                       LONGUS COLLI.

   This muscle, b, b, lies behind the oesophagus, and the great
vessels and nerves of the neck.   Superiorly it is attached to
the tubercle on  the interior arch of the atlas ; inferiorly to the
anterior surface of the bodies of the  first three dorsal and last
four cervical vertebrae, to the intervertebral  fibro-cartilages, and
to the  anterior border of the transverse processes of the third,
fourth, and fifth cervical vertebrae.
   The anterior surface is covered by  the rectus capitis anticus
major, the  pharynx, the carotid artery, the  pneumo-gastric and
great sympathetic nerves, and the oesophagus.  The posterior
surface covers the vertebrae  and their  fibro-cartilages to which
it is attached : on a level with the first two dorsal vertebrae, its
external border is separated from the anterior scalenus by a tri-
angular space lodging the vertebral artery and vein.
   The office of this muscle is to support the neck, to  bend it
forward and to one side.


                   LATERAL CERVICAL REGION.

                    SCALENUS ANTICUS.

  This muscle, c, is situated at the inferior and lateral part of
the neck.   It is elongated and divided above  into several  por-
tions ;  superiorly it is attached by tendons to the anterior tuber-
cles of the  transverse processes of the third, fourth,  fifth, and
sixth cervical vertebrae; inferiorly to the superior border of A,
the first rib.
  vol. i.              26 
194
MUSCULAR  SYSTEM
  On the anterior surface of this muscle we find the subclavian
vein, transverse and ascending cervical arteries,  the diaphrag-
matic nerve, the omo-hyoideus and the sterno-cleido-mastoideus
muscles.  The posterior surface forms with the following mus-
cle  a triangular space, in which are lodged the subclavian artery
and those cervical nerves which form the brachial plexus.  The
inner side is separated  from the longus colli by the vertebral
artery and veins.
  This muscle bends the head and neck  laterally,  and raises
the first rib.


                     SCALENUS POSTICUS.

  This muscle, d, is  placed behind the preceding ; superiorly
it is attached to the posterior tubercle  of the transverse pro-
cesses of the last  six cervical vertebrae, by six small tendons;
inferiorly to the surface of the first rib, and,  to the superior border
of the second rib.
   The anterior surface of this  muscle is connected with the
preceding muscle,  from which it is separated by the subclavian
artery and the anterior  branches of  the  cervical nerves; the
posterior surface is  connected  with the transversus  cervicis,
splenius, and levator scapulae muscles ;  on the inner side with
the first dorsal and summit of the lower six transverse cervical
processes.
   The anterior and posterior scaleni muscles bend the neck  to
one side ; but  when the muscles of both sides act  they  incline
the neck forwards  ; or when the neck is fixed,  they have the
power of raising the  ribs and expanding the chest.


                 RECTUS CAPITIS LATERALIS.

    This is a short, flat, and  thin muscle, /  extending from the
occipital  bone to the transverse  process of the atlas. 
OF THE  TRUNK.
195
  It is connected anteriorly with the jugular  vein; posteriorly
with the vertebral  artery.
  This muscle bends the head sideways.
            CHAP.  IV.


MUSCLES OF  THE  TRUNK.

     ANTERIOR  THORACIC  REGION.

        PECTORALIS  MAJOR.

              Fig. 123.
  This muscle is very large ;  its triangular form and the direc-
tion of its fibres are marked in  the figure at a, b, c.   1 st, it is
attached to the inner half of a, the clavicle ; 2d, to the middle
part of c, c, the whole length of the sternum ;  3d, at b, to  the
cartilages of the true ribs, excepting the first, and a little to the
bony portion of the fifth  rib;  and lastly, from  an aponeurosis
common to it with the abdominal  muscles.   The  fleshy fibres 
196
MUSCULAR  SYSTEM
run obliquely across the breast, and converging  form a small
tendon which is fixed to the outer border of the bicipital groove
of the os humeri.
   This tendon  is shown in Fig. 124, broad and folded upon
itself, and is thus composed of two  laminae, which with the in-
sertion into the humerus on the inner side of g, the long tendon
of the biceps, is very apparent.
   The anterior surface of the pectoralis major is covered by
the platysma myoides, see Fig. 119, by the  mammary gland,
and common integuments.  The posterior surface is situated on
the sternum,  the cartilages of the ribs,  a part of their osseous
portions, the  thoracic vessels  and nerves, the subclavius, pecto-
ralis minor, external intercostal,  serratus magnus, rectus, and
obliquus  abdominis muscles.   On the axilla it is connected with
the axillary ganglia, the  axillary vessels, the nerves of the bra-
chial plexus,  and a considerable quantity of cellular tissue.
   The pectoralis major is a most powerful muscle in moving
the arm ; it carries the arm inwards and forwards, and when it
lowers it, as in striking a blow.   "When the humerus  is fixed it
acts upon the thorax, and becomes  a muscle  of inspiration; or
it can raise the trunk upon the limbs, when holding by  the hands
in climbing a tree, &c. 
OF THE TRUNK.                 197
PECTORALIS  MINOR.

      Fig. 124.
  This muscle, a, b,  c, d,  is situated behind the  preceding
muscle; its shape and the direction of its  fibres are obvious in
the figure.  Superiorly it is attached by a strong flat tendon to
d, the coracoid process of the scapula ;  inferiorly by three di-
visions at a, b, c, to the third, fourth, and fifth ribs.
  The anterior surface is covered by the  preceding muscle;
between them we find some of the thoracic vessels and nerves.
The posterior surface is connected with the ribs, the external
intercostals, the serratus magnus, the axillary vessels, and  the
brachial plexus of nerves.
  The pectoralis  minor draws the shoulder bone  forwards and
downwards, and when that bone is fixed it elevates the ribs. 
198
MUSCULAR  SYSTEM
SUBCLAVIUS.


  Fig. 125.
  This muscle, a,  is placed obliquely under the clavicle.  It
is attached by its external extremity to the inferior surface of b,
the clavicle ; by its internal extremity it is fixed by a flat ten-
don at c, to the cartilage of the first rib.*
  The anterior surface  of the subclavius  is  covered by the
pectoralis major; between them we observe a thin aponeurosis
extending from the  clavicle and coracoid process of the scapula
towards  the first  rib.   The  posterior surface is placed upon
the axillary vessels and the nerves of  the brachial plexus; in-
deed, these  separate it from the first rib.
  This muscle brings forward  and downward the clavicle, and
consequently the shoulder.
* d the sternum. 
OF THE  TRUNK.
199
LATERAL THORACIC REGION.
SERRATUS  MAGNUS.
  The serratus magnus is situated on the side of  the chest.
The form of this muscle  and the direction of its fibres are rep-
resented in  the figure ; but as part of it lies between the blade
bone and the ribs, the  collar bone is here divided at d, e, and
the  blade bone thrown back  from  the trunk.  The  serratus
magnus is anteriorly attached to eight or nine  of the first ribs, 
200
MUSCULAR SYSTEM
a, a, a, a, a, a, a, a, by as many digitations ; posteriorly to
b, b, b, the  whole length of the base of the scapula.*
   The outer surface  of this muscle  is  covered  by the two
pectoral muscles, the latissimus  dorsi,  and  subscapularis, the
axillary vessels,  and the brachial plexus ; the  inner surface is
placed over seven or eight  of the first ribs, the corresponding
external intercostal muscles, and a  portion of the serratus pos-
ticus.
   The office of  this muscle is  to bring  the scapula forward;
when that bone is fixed, it becomes  a  muscle  of  inspiration :
the obliquity of its fibres contributes  to raise the ribs.

                     INTERCOSTAL  REGION.
                           Fig. 127.
  */, the inferior portion of the levator scapulae, g, the inferior portion of
the scalenus anticus, 6, b,b, c, the subscapularis. 
OF  THE  TRUNK.
201
                INTERCOSTALES  EXTERNI.

                          Fig. 127.

  These muscles are the external layers of fleshy fibres which
fill up the space between the ribs, a specimen of which is marked
a.  They are attached on one part to the inferior border of the
rib ;  on the  other, to the  superior border of  the rib beneath ;
the fibres are oblique from above  downwards  and from behind
forwards.
   The outer surface of these muscles is covered by the pectoral
muscle, serratus magnus, obliquus  externus abdominis, serratus
posticus superior and  inferior,  and sacro-lumbalis.  The inner
surface is in contact with the pleura, from the tuberosity as  far
as the angle of the ribs ; in the rest of their extent they are  in
contact with the internal intercostal muscles.
                INTERCOSTALES  INTERNI.

  These muscles, a specimen of which is marked b, are similar
in number and in  situation  to the preceding.   They extend
from the inferior margin of one rib to the superior margin of the
rib below, and from the spine to the breast bone.   They differ
only in having the fibres pass  obliquely from above downwards
and from  before backwards.
  The outer surface of this set of  muscles is  covered by the
preceding muscles, and is in contact  with the intercostal vessels
and nerves.   The inner surface is  lined by the pleura.
  The intercostal muscles are two sets of muscular fibres, the
one external,  a, the other internal, b, passing in contrary direc-
tions, as the old anatomists describe  them, like St.  Andrew's
  vol. i.            27 
202
MUSCULAR SYSTEM
cross;  excepting that  between the  cartilages of the ribs, see
Fig. 126, there is merely the internal  layer, and  at  a small
space from the spine the external layer only.
   The  offices of both the external and internal intercostals are
the same ; they elevate or depress  the ribs, in  the motions of
inspiration or expiration, according as the upper or lower attach-
ment is the line from which they act.
                   LEVATORES COSTARUM.

      Fig-128-             These  are  twelve  very small  thin
        6              triangular muscles on either side of the
                       dorsal vertebrae ;  they appear as if they
                       were portions of  the external intercos-
                       tals.   Each muscle  is attached superi-
                       orly to the  transverse process of the
                       lowest  cervical and  the eleven upper-
                       most dorsal  vertebrae ; inferiorly to a
part of the upper  border of the  rib next below.*  Three or
four of the inferior elevators, however, are longer than the others,
and run down over one rib,  to be attached to the alternate rib;
hence Albinus denominated this set of muscles levatores cos-
tarum breviores  et longiores.
   The action of these muscles assists in  raising the ribs and in
supporting the spinal column.

  * A specimen of these muscles is given in the figure; b, the transverse
process ; a, the rib.  The whole are represented in Fig. 143, b, b, b, b,b, b,b.
 
OF THE  TRUNK.
203
TRIANGULARIS  STERNI.


        Fig. 129.
  This muscle is situated within the thorax, behind the carti-
lages of the ribs.   It is attached on the outer side at a, b, c, d,
by four triangular tendinous and fleshy portions, to the  cartila-
ges of the third, fourth, fifth, and sixth ribs :  on  the inner side
to the posterior and inferior part of e, the sternum, and  at/ to
the ensiform cartilage.
  We have here a posterior view of the triangularis sterni, and
this surface is covered by the pleura, and a small part by  the
diaphragm.   The anterior surface is covered by  the cartilages
of the ribs, the inner intercostal muscles, and internal mammary
vessels. 
204
MUSCULAR  SYSTEM
  This muscle depresses the cartilages and lowers the extrem-
ities of the ribs, and is consequently subservient to expiration.
REGION OF THE DIAPHRAGM.
DIAPHRAGMA.
   This is a broad, thin muscle, dividing the cavity of the chest
from the abdomen.   Its  form is  nearly  circular, it is fleshy 
OF THE  TRUNK.
205
at its circumference, aponeurotic  in  the middle.   The direc-
tion of its radiated fibres is represented in this figure.   Anteri-
orly it is attached at  o, to the ensiform cartilage; laterally to
the internal surface of the cartilages of the six last ribs; poste-
riorly to the transverse processes of the first lumbar vertebra ;
by its left pillar at c* to the bodies of the three first vertebra?
of the same region ;  by its right pillar at d, to the bodies of the
first four.   The structure of the diaphragm  consists  in part of
a  three-lobed  aponeurosis, b, b,  termed  the  phrenic centre,
having an opening for  the  vena cava, /;  it is fleshy at  a, a, a,
in the rest of its extent, and presenting  posteriorly two open-
ings,  one at m, for the oesophagus and pneumo-gastric nerves,
the  other  traversed by n, the  aorta;  the vena azygos  and
thoracic duct, also pass through it.
   The upper surface of the diaphragm is connected with  the
pericardium, the  mediastinum, and the pleura; it  supports  the
heart and the base of the lungs.   The lower surface  posteriorly
is in contact with  the kidneys, the surrenal capsules, the pan-
creas, and the duodenum ;  on the right side with the liver ; on
the left side with the spleen and stomach ; in its whole extent
it is covered by the peritonaeum.
   The diaphragm performs a most important office in the phe-
nomena of respiration ;  every  time we draw in  our breath it
contracts, and changing its vaulted form  to that of a  plane, it
enlarges the capacity of the chest so as to admit of the dilatation
of the lungs ; it may therefore be called  the  principal  muscle
of inspiration.   On the other hand,  when,  it relaxes, the ab-
dominal muscles  press their  viscera upwards,  and  the dia-
phragm  ascends in the thorax and  compresses  the lungs,  and

  * Termed also tendinous feet, or crura, c, d, e,f. These feet or crura run
obliquely  upwards  and forwards into  two  fleshy portions called alae, which
raixing^and crossing fibres terminate in b, b, the tendinous centre. 
206
MUSCULAR  SYSTEM
thus contributes to expiration.  It also acts in coughing, vom-
iting, laughing, and speaking, and assists in various other func-
tions, as in the expulsion of the contents of the uterus, bladder,
and intestines.
  The motion of the  diaphragm is moreover subservient to
snuffing odors, to sighing,yawning, coughing,  sneezing, hiccup,
and all those actions connected with inspiration and expiration. 
OF THE TRUNK.
207
MUSCLES   OF  THE  ABDOMEN.






             ABDOMINAL REGION.






     OBLIQJJUS ABDOMINIS EXTERNUS.




                   Fig. 131.
This muscle is  situated  on  the anterior and lateral parts of 
208
MUSCULAR  SYSTEM
the abdomen ;  its figure is broad, thin, and  irregularly quadri-
lateral.    It  is  attached superiorly  by fleshy triangular slips,
called digitations, to  the external surface and inferior margin
of the seven or eight last  ribs; inferiorly to the two anterior
thirds of the edge of the hip bone.   The muscular fibres, i,
are directed obliquely from above  downwards and from behind
forwards, and about the middle terminate abruptly at b, b,  the
semicircular line (linea  semicircularis,) which runs  from  the
pubis to the ribs.   A flat tendinous  expansion or aponeurosis
is  then continued to meet  with  that  on  the  opposite side,
where it forms  a central tendinous cord, a, a, termed the white
line (linea alba), which extends  from  the ensiform cartilage
to the pubis.   This line appears to be the result of the reunion
of the aponeuroses of the  two oblique and transverse muscles
upon the median  line of the abdomen ;  and it is composed of
inextricable fibres of a very strong texture, forming a kind of
ligament to unite the sternum to the pelvis.   There  are lines
of a similar nature, passing from the linea semicircularis to  the
linea alba, marked with  the letters c, c, and termed linea trans-
versales.  The letter d, marks the umbilicus or navel, consist-
ing of condensed cellular membrane : in the foetus it was a for-
amen which gave passage  to the  nutrient vessels, which con-
nected  the  foetus with  the  placenta.   Inferiorly the external
oblique muscle is fixed  to Poupari's ligament, which appears
like a strong  resistant fold stretched from  the  anterior superior
spine of the ilium to the pubis.  Near this  insertion there is a
small oblique opening at e,  formed  as it were by the splitting
of the aponeurosis ; it is named the abdominal ring: it allows
the spermatic cord in the male, and the round ligament of  the
uterus in the female,  to pass through it.  The fibres being
again united, cross each other, and are inserted into the pubes.
This opening  is likewise strengthened  by tendinous fibres,
which pass  transversely, and in various  directions, forming it
into an elliptical aperture. 
OF THE  TRUNK.
209
  The outer surface of this muscle is covered by the common
integuments, and at the back part by the latissimus dorsi;  the
inner surface  is placed  on  the anterior  part of the last eight
ribs and their cartilages, the corresponding intercostal muscles,
and the obliquus internus.
             OBLIQUUS ABDOMINIS INTERNUS.

  This muscle, Fig. 131,/ is placed  behind  the preceding,
and like it is broad, thin, and  somewhat  quadrilateral.   It  is
attached superiorly to the border of the cartilages of the eighth,
ninth, tenth, and eleventh  ribs ; inferiorly, to the  spine of the
ilium, to the crural arch, and to the pubis ; posteriorly, to the
spinous processes of the lumbar vertebrae,  and to the  sacrum ;
anteriorly, to the linea alba.   The  figure  expresses by its lines
the direction of the fibres ;  viz., the superior fibres are oblique
from below  upwards, and from behind forwards; the middle,
horizontal;  the inferior,  a little oblique from above down-
wards.  The muscle becomes aponeurotic at the linea  semi-
circularis, and adheres firmly to it, then divides into two layers.
The anterior layer unites  with  the tendon  of the  external
oblique, the internal adheres to the muscle behind it;  they in-
close  a  long muscle, k, k, and  are  finally  reunited  at  a,  a,
the central  linea  alba.   The anterior tendon is here  removed
to show the rectus muscle.
  The outer surface is covered by the preceding muscle and
by the latissimus dorsi; the inner surface is in contact  with the
transversalis  abdominis  and sacro-lumbalis.
vol. i.                     28 
210
MUSCULAR  SYSTEM
TRANSVERSALIS ABDOMINIS.
  This muscle  is  situated  behind  the oblique  muscles; its
form is similar, and it is attached superiorly to d, the cartilages
of the seven lower ribs ; inferiorly, to the crest of b, the ilium,
and at  c, to the two  internal thirds of the crural arch; posteri-
orly, to the summit of  the  transverse and  spinous processes of
92 
OF THE  TRUNK.
211
the four  first  lumbar  vertebrae.  The  fleshy fibres proceed
transversely, and end in e, a flat sheet of tendon or aponeurosis,
which, after being connected to the tendons of the two oblique
muscles at the semicircular line, it then divides into two lam-
inae to form a sheath for the  rectus abdominis ; the anterior
lamina is united with the aponeurosis of the  external oblique
muscle, and is extended over the front of the rectus ; the pos-
terior lamina is united with the aponeurosis of the internal ob-
lique, and  is extended behind the  rectus, excepting  at its
lower part; for at the  middle distance between  the  umbilicus
and pubes, a  slit or fissure is formed at h, in the  aponeurosis of
the  transversalis, through  which  the  rectus  passes,  so that
the remainder of the aponeurosis passes before the rectus, and
is anteriorly inserted into /  the ensiform cartilage, and g, the
linea alba.   The external surface of  this muscle is covered by
the obliquus internus, the internal by the peritonaeum.
                    RECTUS ABDOMINIS.

  This muscle, Fig. 131, fc, k, Fig. 132, i,  is situated imme-
diately in front of the abdomen, on each side of the linea alba,
under the anterior  laminae of the tendons of the oblique  mus-
cles.  The rectus abdominis  is long and flat, and is attached
superiorly to the cartilages of the fifth, sixth, and  seventh ribs,
and to the ensiform  cartilage ;  inferiorly to  the  pubes.   It
is divided by  three or  four tendinous intersections, marked in
Fig. 131, c, c, denominated  the  transverse lines ;  by these di-
visions the muscle  is connected firmly  to  the  anterior part of
the  sheath, while it adheres very slightly by  loose  cellular sub-
stance to the posterior layer.
  The anterior surface of this muscle is covered by the apon-
eurosis of the  pectoralis major, and by a lamina of  the  abdomi-
nal  aponeurosis, except at the  lower part, where we commonly 
212
MUSCULAR  SYSTEM
find  the pyramidalis.  The posterior surface is extended over
the cartilages of the last three true ribs, a portion  of the carti-
lages of the last two false ribs,  the ensiform cartilage, the pos-
terior fold of the abdominal aponeurosis, the internal mammary
and  the epigastric arteries, and the peritonaeum.
   The office of the last-mentioned muscles, viz., the external
and  internal oblique, the  transversalis, and  rectus, is  to draw
down the ribs in expiration: to bend  the body obliquely, or to
one side when one set acts singly, but when  they  act together
they bend the thorax directly forwards.  They have the power,
when the ribs are fixed, of raising the pelvis ; they also com-
press the abdominal viscera, so as to raise the diaphragm and
expel the air from  the lungs; lastly,  they assist in the expul-
sion of the foetus, urine and faeces.
                        PYRAMIDALIS.

   This is a very small muscle, Fig. 131, A, placed  over  the
pubes.   It is attached  superiorly, near  half-way between the
pubes and umbilicus, to the linea alba; inferiorly to the pubes.
   It is connected  anteriorly  with the abdominal aponeurosis;
posteriorly with the rectus abdominis.
   This muscle merely assists  the recti muscles. 
OF  THE  TRUNK.
213
LUMBAR REGION.






PSOAS  MAGNUS.






    Fig. 133.
This muscle, g, g, is situated on the side and lower part of 
214
MUSCULAR  SYSTEM
the vertebral column.   It is  attached superiorly,  at e, to  the
last vertebra of the back,  and at h, i, k, I, to the four superior
vertebrae of the loins ; inferiorly, at m, to the smaller trochan-
ter of the os femoris.
   The anterior surface of the psoas magnus is connected with
the diaphragm, peritonaeum, kidney, psoas parvus, external iliac
artery,  crural  artery and  vein ;  the inner side  with the  bodies
of the lumbar vertebrae and the  fibro-cartilages which  separate
them, and with the  external iliac vein and the pectineus; the
posterior surface with the quadratus lumborum, lumbar nerves,
and the anterior lamina  of the aponeurosis of the transversalis
abdominis.  Lower down it  is  connected with the os ilii and
the capsular ligament  of the hip joint.
   This muscle is a flexor of the  thigh on  the pelvis, bending
the thigh forwards,  and rolling  it outwards ; or if the inferior
extremities are fixed, it will assist in bending the body.
                       PSOAS PARVUS.

   This muscle, d, does not exist in every subject; it is small
and thin,  and placed before the preceding muscle.   It is at-
tached superiorly, at e, to  the last dorsal vertebra and fibro-
cartilage, which separates it from h, the first lumbar vertebra;
inferiorly, at/  to the brim of the pelvis.*
   The anterior surface of the psoas parvus has the diaphragm,
renal vessels and nerves,  the peritonaeum, and the external iliac
artery, extending over it; the posterior surface is united in its
whole extent by the cellular tissue to  the psoas magnus.
   The contraction of this muscle will assist the great muscle
in bending the body forwards on the pelvis.
* This edge is also named the linea ilic-pectinea. 
OF THE  TRUNK.
215
                    ILIACUS  INTERNUS.

  This muscle, o, is placed in the cavity of  the ilium,  from
which it is named ; it is large, thick, and radiated. It is attached
superiorly, at p, to  the two anterior  thirds of the crest of the
ilium, and to the principal part of the  concave surface of that
bone ; its converging fibres join g, the  psoas magnus, and are
inserted inferiorly with it by one  common tendon  into (m) the
small trochanter  of the thigh bone.
  The anterior surface of this muscle is covered  above by the
peritonaeum on the right, and by the coecum ; on the left, by the
sigmoid flexure of the colon ; more inferiorly, that is, below the
crural arch, by the sartorius, the pectineus,  and  by the crural
vessels and  nerves.  The  posterior surface is extended  over
the iliac  fossa,  the superior part of the rectus femoris, and the
hip joint.
  This muscle powerfully assists in bending the  thigh on  the
pelvis, or the latter  on the  thigh ; it acts strongly in progres-
sion, and in maintaining the body in the erect position.
                  QUADRATUS LUMBORUM.

  The name of this muscle, a, a, is expressive of its figure and
situation.  It is attached superiorly, at b, to  the last rib ; infe-
riorly, at c, to the posterior part of the crest of the ilium, and to
the ilio-lumbar ligament;  and on the inner side, by tendons, to
the transverse processes of the four first lumbar vertebrae.
  This muscle has the power of inclining the body to one side ;
if both muscles act, they are  flexors of the chest upon the hips,
and reciprocally the pelvis upon the trunk. 
216
MUSCULAR  SYSTEM
 ANAL REGION.

LEVATOR ANI.

   Fig. 135.

   0  p   q
  This muscle, k, with its fellow, is a sort of concave floor to
the abdominal and pelvic cavity, or it may  be compared to a
shallow funnel surrounding the extremity of the  intestine.  It
is very thin, and is attached superiorly to the inner part of the
pubes, to the superior part of the obturator foramen, and to the
spine of  the ischium ; inferiorly, the middle and  anterior fibres
unite beneath the rectum enveloping  this intestine ; the most
anterior seem attached to the prostate gland  ; other fibres spread
forwards on the commencement of the urethra, and  backwards
to n, the os coccygis, forming  a tendinous line. 
OF THE  TRUNK.
217
  The outer surface of this muscle is connected by a layer of
cellular tissue  to  the gluteus maximus, the obturator internus,
and transversus perinaei.   The inner surface is connected with
the bladder, prostate gland and lower part of the rectum.
  The use of this muscle, as its  name implies, is to draw up
the rectum after its contents have been expelled.
                       COCCYGEUS.

  This is a thin, flat, triangular muscle, / attached on the one
part to g, the spinous process of the ischium ; its fibres diverge,
and are inserted on the other part into n, the border of the  os
coccygis, and into h, the extremity of the sacrum.
  The posterior surface of  this muscle, which inclines down-
wards, is covered by the sacro-sciatic ligaments ;  the anterior
is connected to the rectum by cellular tissue.
  This muscle moves the coccyx,  and secures it in its situa-
tion.
                     SPHINCTER ANI.

  This muscle, e, is of an oval figure, open in its centre ;  its
fibres surrounding the extremity of the  rectum or anus are ac-
curately expressed in the figure.   It is attached, at n, to the os
coccygis, by a  species of cellular tendon,  from  whence two
fleshy fasciculi proceed,  uniting together in front of the anus.
  The upper  surface is connected with the  levator ani  by
cellular  tissue ; the lower surface is  covered by the common
integuments.
  This  muscle closes  the anus, and in the male draws down
the bulb of the urethra.
  vol. i.                      29 
218
MUSCULAR  SYSTEM
                  GENITAL  REGION.

                        I. IN THE HALE.

                         CREMASTER.

   This muscle consists of a few scattered fibres, sent off by the
 obliquus internus abdominis, over the spermatic  cord, and ex-
 panded upon the  tunica  vaginalis testis.   For a view of this
 muscle we must refer back to Fig. 131, g.
   This muscle draws up the testis.


          ISCHIO-CAVERNOSUS, OR  ERECTOR PENIS.

   This,is a small, elongated muscle, c, placed along the ramus
 of the ischium,  and root of  o, the  corpus cavernosum.  It is
 attached on the one part to the tuber ischii, and  on the other
 part to the fibrous membrane of the corpus cavernosum.
   The outer surface corresponds  with the ramus of the ischium;
 the inner is connected with the transversus perinaei and bulbo-
 cavemosus.
   This muscle draws the root of the penis downwards and
 backwards.


       BULBO-CAVERNOSUS,  OR ACCELERATOR URINJE.

  This muscle, d, is situated beneath the bulb of the urethra,
and covers part of p, the  corpus  spongiosum.  It is attached
to these parts, and its  fibres  are  confounded with the muscles
of the anal region;  but it is separated from  its fellow muscle
by a tendinous line. 
OF THE  TRUNK.
2\J
  The superior surface covers the  bulb and  commencement
of the spongy portion of the urethra and corpus cavernosum ;
the inferior surface is connected with the  preceding muscle
and common integuments.
  This  muscle compresses  the posterior part of  the urethra,
and urges  forward any fluid which  that canal may contain;
hence it has been  sometimes  denominated  accelerator urinae,
vel ejaculator seminis.
                 TRANSVERSUS PERINAI.*

  This is a flat and thin muscle, I; the name indicates its sit-
uation.  It is  attached on  its outer part to the  ramus and
tuberosity of the ischium ;  on the inner part to the middle line,
with its fellow on the opposite side.
  The exterior surface is covered  by  the  common integu-
ments ; its other relations may be seen in the figure.
  This muscle  is  supposed to dilate the urethra ;  it certainly
supports the lower part of the bladder and rectum.
  There is  frequently another  slip  of  muscular fibres, taking
the same course, termed transversus perinai alter.
                    II. IN THE FEMALE.

      ISCHIO-CAVERNOSUS, OR  ERECTOR  CLITORIDIS.

  This muscle is  similar to that just  described  in the other
sex, but is much smaller.  It is  attached on the outer side to
the tuber ischii;  on the inner it  terminates by embracing  the
cavernous body of the clitoris.
* The perimeum is that space which is between the genitals and anus. 
220
MUSCULAR  SYSTEM
CONSTRICTOR VAGINJE.
Fig. 136.
  This muscle, a, consists of a  number of muscular  fibres,
forming a sort of broad fleshy ring surrounding the vagina.*
  This muscle contracts the part which it embraces.
" b, the pubis, c, the bladder, d, the uterus, e, the rectum. 
OF THE TRUNK.                  221
MUSCL2S  OF  THE POSTERIOR  PART OF  THE TRUNK.





                 LOMBO-DORSAL REGION.





                      TRAPEZIUS.





                        Fig. 137. 
222
MUSCULAR  SYSTEM
   The trapezius is a broad, flat muscle, a, b, d, and Fig.  138,
a, e, d, situated at the  posterior part of the neck,  shoulder, and
upper  part of the  back.  It is attached superiorly, at a, the
superior transverse line of the occipital bone, and to the cervi-
cal ligament, and to the spinous process of the seventh cervical
vertebra; inferiorly to the spinous processes of  all the dorsal
vertebrae; on the outer side to d,  the spine of the scapula,  and
the edge of this muscle slides over e, a triangular space at the
extremity of that bone, to the acromion, and to c, the external
third of the clavicle.   The direction of the  fibres is shown by
the lines  of the engraving.
   The posterior surface of the trapezius is entirely  covered by
the common integuments ; the anterior surface is connected at
its upper and  inner part with  the  complexus major;  further
down  with the splenius,  levator anguli scapulae,  and serratus
posticus superior ; at its lower part it covers  the supra-spinatus,
infra-spinatus, rhomboideus, latissimus dorsi,  and sacro-lumbalis
muscles.
   When all the fibres of this  muscle act simultaneously, they
draw back the scapula  and clavicle  ; the upper fibres will ele-
vate the tip of the  shoulder,  the lower  will move it backwards
and obliquely downwards.   If the shoulder  is fixed, the trape-
zius has the power of inclining the head to one side.
                    LATISSIMUS  DORSI.

   This is a large, thin, flat muscle, placed on the back and side
of the lower part of the trunk. It is attached superiorly, at /, to
the inner edge of  the groove in the os humeri,  which receives
the long tendon of the biceps; inferiorly, to the posterior half
of g, the external border of the crest of the ilium, and at /, to
the back and upper part of the sacrum ;  on the inner side it is 
OF THE TRUNK.
223
fixed to the  spinous  processes  (from b to Z) of all the lumbar
vertebrae, and to those of the six or seven lower dorsal; on the
outer side to the four last ribs, at n, n, n, n, by as many digita-
tions.   The direction of the fibres is expressed in the figure ;
they are aponeurotic at  the internal and inferior part of the mus-
cle, tendinous at its insertion into the humerus,  and fleshy  in  ^**
other parts.   The superior edge  passes over the  inferior angle
of the scapula at m, and sometimes has a slip attached to it, and
the margin at/ forms the fold of  the back part of the arm-pit.
This muscle is also represented in Fig. 138, at b.
   The posterior surface of this muscle is covered by the integ-
uments, excepting at its upper and inner part, which is covered
by a, d, b, the trapezius.  The  anterior surface is connected
with the obliquus abdominis, serratus  posticus  inferior, sacro-
lumbalis, levatores costarum, external  intercostal muscles,  the
serratus magnus, rhomboideus, teres major, infra-spinatus, the
 lower  ribs, and the inferior angle of the scapula.
   The office of the  latissimus dorsi is to carry the arm back-
 wards  and downwards ;  or when the hand is fixed, to bring for-
 ward the body. 
224
MUSCULAR  SYSTEM
DORSO-CERTICAL  REGION.






    RHOMBOIDEUS.






       Fur. 138.
The situation and form of this muscle, *,/, is clearly exhib- 
OF THE  TRUNK.                 225
ited in the figure.   It is attached by its internal margin to the
posterior cervical ligament, to the spinous process of the seventh
cervical vertebra, and to those of the four or  five first dorsal •
by its internal margin, at „, to all the base of the scapula below
o, the spine of that bone.  This muscle is divided by a cellular
line into two portions :  therefore frequently denominated,/ the
rhomboideus major, i, the rhomboideus minor.
  The posterior surface of the  rhomboideus  is covered by  the
trapezius and latissimus dorsi; the anterior surface covers  the
serratus posticus  superior, the splenius, the sacro-lumbalis,  the
ribs and external intercostal  muscles.
  The action of this muscle is to bring the scapula  obliquely
upwards and directly backwards.
VOL. I.
30 
226
MUSCULAR  SYSTEM
LEVATOR SCAPULA.

      Fig. 139.
  This is a long, thick muscle, a, placed at the side and back
of the neck.   It is attached superiorly to the transverse proces-
ses of four or five of the superior vertebrae of the neck, by dis-
tinct tendons ;  these unite and form a strong muscle, which is
fixed inferiorly into the base of the scapula above e, the spine.
See also Fig. 138, A.
  The outer surface of this muscle is covered on the upper part
by the sterno-cleido-mastoideus, in the middle by the skin, and 
OF THE  TRUNK.
227
below by the trapezius.   The inner surface is connected with
the serratus posticus superior, the sacro-lumbalis, and splenius.
   This muscle raises the posterior angle  of the scapula,  and
consequently depresses the tip of the shoulder;  it has the power
also of inclining the neck  to one side, or maintaining it  in  an
erect position when it acts in conjunction with  its fellow.
               SERRATUS POSTICUS  SUPERIOR.

   This muscle, g, is very thin ; its situation and form are delin-
eated in the figure.   It is attached by its internal border to the
posterior cervical ligament,  to the spinous process of the last
cervical vertebra, and to those of the three upper  dorsal;  out-
wardly, by distinct fleshy portions, or digitations, into the sec-
ond, third, fourth, and  sometimes the fifth ribs,  a little  beyond
the angle.
   The posterior surface is  connected  with  the rhomboideus,
the levator anguli scapulae, serratus magnus, and trapezius ; the
anterior surface with the splenius, longissimus dorsi, transversa-
lis colli, sacro-lumbalis, ribs, and the  external  intercostals.
  The action of this muscle dilates the thorax, by elevating the
ribs.
               SERRATUS  POSTICUS INFERIOR.

   For the form of this muscle, the reader is referred back to the
preceding engraving, Fig. 138, I.   It is situated at the inferior
part of the back, and, like the serratus  superior, is  broad and
thin.   It is attached by its inner border to the spinous processes
of the two lower dorsal  vertebrae,  and to those of the  three
upper lumbar;  at its outer border,  by distinct  slips,  into the
four inferior ribs. 
228
MUSCULAR  SYSTEM
  The posterior surface is connected with the latissimus dor-i;
the anterior surface with the three lower ribs, the correspond-
ing intercostal muscles, and the posterior lamina of the aponeu-
rosis of the transversalis abdominis.
  This muscle depresses the ribs, and draws them backwards.
                          SPLENIUS.

   This muscle,  Fig. 138,  k, Fig.  139, b, c,  d, is  placed
obliquely at the back of the neck;  its form  is elongated and
flattened.   It is divided by a line of cellular membrane into two
portions, which have sometimes  been considered  as  two mus-
cles, and  in the last-mentioned figure is attached  superiorly  at
b, to the mastoid process of the temporal bone, and at c, to the
occipital bone immediately below the superior transverse ridge;
inferiorly, at d, to the last cervical  and six upper  dorsal verte-
bra;.
   The external surface  of the splenius is connected  with the
sterno-cleido-mastoideus, the trapezius,  levator anguli scapulae,
serratus posticus superior,  and  rhomboideus ;  the  internal sur-
face with the great and little complexus.
   The contraction of this  muscle will turn the head, or incline
the head and neck completely backwards  ; when both muscles
act together, they bend the head directly backwards. 
OF THE TRUNK.
COMPLEXUS.
Fig. 140.
   The situation and form  of this muscle,  a,  is obvious in the
figure before us.   It is attached superiorly, at b, between the
transverse ridges of the occipital bone; inferiorly, by isolated
fasciculi of  tendinous  and fleshy fibres, at c, c, c,  c, c, c, to the
transverse and articular processes of the last  six  cervical ver-
tebrae, and at e, e,  e, e, to the transverse processes  of the four or
five first dorsal vertebrae.  These  attachments are frequently
confounded with those of the transversus colli.
   The external surface is connected with the trapezius, sple-
nius, and  trachelo-mastoideus ;  the  internal  with  the  semi- 
230
MUSCULAR SYSTEM
spinalis  colli,  the  arteria  cervicalis profunda,  the posterior
branches of the  cervical nerves,  the  rectus  capitis  posticus
minor, and the obliquus capitis inferior.
   This muscle,  draws  the head  backwards and to one  side.
When the two act together,  the face is turned upwards.
TRACHELO*-MASTOIDEUS.

         Fig. 141.
   This muscle is much smaller than the preceding, and is placed
on its outer edge.   It is attached superiorly at a, to the poste-
rior part of the mastoid process of the temporal bone ; inferiorly,
at b, to the transverse processes of the four last cervical verte-
brae, and sometimes,  at c, to the first dorsal, by distinct tendi-

  * So called from a Greek word for the spine.  This and the former mus-
cles are as frequently denominated complexus major et minor, and their re-
semblance may be seen by comparing the figures before us. 
OF THE  TRUNK.
231
nous and fleshy fasciculi.   The  trachelo-mastoideus  is  also
connected at its inner edge by a fleshy band to the longissimus
dorsi.  Both this  and the preceding muscles  are  traversed by
aponeurotic  intersections or bands, varying  in direction  and
position.
  The outer surface  of this muscle  is connected with  the
splenitis and transversalis  colli ; the inner with the complexus
and obliquus capitis,  the  posterior extremity of the digastricus,
and the occipital artery.
  The action  of this muscle keeps the head erect, or  inclines
it a little backwards or to one side, without rotation.
 POSTERIOR OCCIPITO-CERVICAL REGION.

RECTUS  CAPITIS  POSTICUS  MAJOR.

              Fig. 142.
  This is a small muscle, a, situated on the upper part of the
back of the neck.   It is attached superiorly to the lower trans-
verse ridge of the occipital bone, and to part of the depression 
232
MUSCULAR  SYSTEM
above that ridge, between the rectus capitis posticus minor and
obliquus capitis superior.   Inferiorly it is fixed to the  spinous
process of the dentata or second cervical vertebra.
  The posterior surface of  this muscle  is connected with the
complexus and obliquus capitis superior ; the anterior surface
with the occipital bone,  the  atlas, the  rectus capitis posticus
minor and the vertebral artery.
             RECTUS  CAPITIS POSTICUS  MINOR.

   This is a very  small muscle, b, attached  superiorly to the
occipital bone behind the foramen  magnum, and  a little to the
side of the inferior curved line ; inferiorly to the  tubercle at
the posterior arch of the atlas.
   The posterior surface  of this  muscle, which is inclined
downwards, is connected with the great  complexus and with
the preceding muscle ; the anterior surface with the occipital
bone, the atloido-occipital ligament, and the  vertebral artery.
                OBLIQJUUS CAPITIS SUPERIOR.

   The relative size and situation of the obliquus capitis supe-
rior, c, is expressed in the figure ; it is attached superiorly to the
outer part of the curved line of the occipital bone;  inferiorly to
the transverse process of the first cervical vertebra, in front of
b, the preceding muscle.
   The posterior surface  is connected  with the  complexus,
the trachelo-mastoideus, and the splenius;   the anterior with
the occipital bone, the vertebral  artery, and the attachment of
the rectus capitis posticus major. 
OF THE  TRUNK.
233
               OBLIQ.UUS CAPITIS INFERIOR.^

  This muscle, d, will be  found  to  resemble very much  the
superior oblique ;  it is attached superiorly to the transverse pro-
cess of the atlas, and inferiorly  to the  spinous process of the
dentata.
  The posterior surface is connected with  the complexus  and
trachelo-mastoideus ; the anterior with the second vertebra, and
with the posterior ligament uniting the axis  and atlas, and with
the vertebral artery.
  The office of the four muscles  just  described, according to
their several directions and obliquity, is to rotate the head, in-
cline it backwards or to one side, and to maintain the head in
the erect position.
                INTERSPINALES CERVICIS.

  There are six very small muscles, at e, e, e, e, e, e, on either
side of the intervals of the spinous processes of the neck.   Each
of them is attached superiorly to the lower  surface of the spi-
nous process, and inferiorly  to the  upper surface  of the next
spinous process below it.
  These  muscles draw the  spinous processes  nearer to each
other,  and consequently incline the head backwards.   Similar
sets of muscles occupy the spaces between the spinous processes
of the vertebrae of the  back and loins; in the  neck, however,
they are double, corresponding to the bifurcations of the spinous
processes.  In the back and loins they are  indistinct, and  are
rather like tendons than muscles.
VOL. I.
31 
234
MUSCULAR  SYSTEM
  VERTEBRAL REGION.





LONGISSIMUS DORSI.





       Fig. 143.
The longissimus dorsi,  d, d,  constitutes part of the thick 
OF  THE  TRUNK.
235
muscular mass which occupies the space between  the spinous
processes of the  vertebrae  and the angle of the ribs.   On the
inner side it is attached by small double tendons to all the trans-
verse processes of the back, and to the last transverse process
of the neck  ; from  its outer side it sends forth fleshy  and  ten-
dinous filaments, which  are inserted into the eight lower ribs.
Inferiorly, it is attached  in common with the sacro-lumbalis.
   The internal surface  of the longissimus dorsi is connected
with the multifidus  spinae, complexus, and transversalis colli;
the external is contiguous to the sacro-lumbalis;  the anterior
is placed upon the levatores costarum,  the  ribs,  the transverse
processes of the  vertebrae, the posterior costo-transverse liga-
ments, the dorsal  vessels  and nerves, and a portion of the  exter-
nal intercostal muscles.   The posterior surface is connected
with the aponeurosis of the obliquus internus and  transversalis
abdominis, serratus posticus superior, latissimus dorsi, trapezius,
rhomboideus, and splenius. 
236
MUSCULAR  SYSTEM
SACRO-LUMBALIS.

    Fis;. 144.
   This muscle, a, a, is situated on  the outer side of b, the
longissimus  dorsi, extending  from the  sacrum  to the neck. 
OF  THE  TRUNK.
237
On the right side of the figure we see it attached on the outer
part of the lower edge of all the ribs, by as many distinct ten-
dons ; on the inner part  we find  it is attached  to the upper
border of nine or ten  of the lower  ribs by as  many tendons.
The muscle on the left  side is  drawn back with the hook, /
to show these  tendons.   There are some portions  of this mus-
cle marked, g, g, which  are inserted into the  transverse pro-
cesses of five or six of the lower cervical vertebras by as many
distinct tendons.   These fasciculi are frequently described un-
der the name of the cervicalis descendens.  The sacro-lumba-
lis is inferiorly fleshy within  and aponeurotic without; and, as
I before observed, forms  one inseparable  muscle with the lon-
gissimus dorsi, which is attached at e, to the sacrum, the poste-
rior spine of the ilium, all the spinous processes, and near the
roots of the transverse processes of the lumbar vertebra?; not
separating  from  b, b,  its  companion just  mentioned, till it
reaches the ribs.
   The anterior surface of the sacro-lumbalis is connected with
the aponeurosis of the transversalis  abdominis,  the ribs,  and
external intercostal muscles, the longissimus dorsi,  and trans-
versalis colli.   The inner side with the longissimus dorsi;  the
outer side with the line of union of  the posterior lamina? of the
aponeurosis of the transversalis abdominis.
   The longissimus dorsi and sacro-lumbalis preserve the verte-
bral column from yielding to the weight placed on it and before
it; in a word,  they are the  most powerful  muscles  that  are
employed in keeping the  body erect.
TRANSVERSALIS COLLI.
  This muscle, Fig. 143, a, lies on the inner side of the lon-
gissimus dorsi, and is indeed sometimes considered as an appen-
dage to it.  It is attached superiorly, by small  tendons, to  the 
238
MUSCULAR SYSTEM
 transverse processes of the second, third, fourth, fifth, and sixth
 cervical vertebrae;  inferiorly it is fixed by tendinous and fleshy
 slips to the transverse processes of the third, fourth, fifth, sixth,
 and seventh dorsal vertebrae.
   The posterior edge of this muscle is blended with the trach-
 elo-mastoideus muscle ; in the middle it is connected with the
 levator  anguli scapulae and the serratus posticus superior, and
 below with the  longissimus dorsi.   The anterior edge is con-
 nected with the transverse  processes of the second cervical to
 the eighth  dorsal vertebra.   The  outer surface  corresponds
 with the splenius, levator  anguli scapulas, and sacro-lumbalis;
 the inner with the complexi and part of the multifidus spinas.
   This muscle turns the neck  obliquely backwards and  to one
 side.


                     MULTIFIDUS  SPINJE.

   The fasciculi, c, c, Fig. 143, composing  this mass  of mus-
 cles, are placed obliquely from  the transverse processes to the
 spinous processes.  They are attached  by distinct tendons to
 all the spinous, transverse, and articular processes of the six last
 cervical  vertebras, the  twelve dorsal, and the five  lumbar, and
 to the posterior surface of the sacrum.*
   The posterior surface of  these muscles is connected with
 the trachelo-mastoideus,  arteria  cervicalis  profunda, posterior
 cervical  nerves,  and  longissimus  dorsi; the anterior surface
 with the plates of the vertebrae, their transverse and oblique pro-
 cesses, and the ligamenta subflava ; on the inner side with the
spinous processes of the vertebrae, the inter-spinalis cervicis, and
 the dorsal and lumbar interspinous ligaments.

  * These have been described by some anatomists  as three distinct sets of
muscles, viz., transverso-spinalis colli, transverso-spinalis dorsi, transver.
so-spinalis lumborum. 
OF THE  TRUNK.                239
  The office of these muscles is to incline the vertebral column
to one side; but when the muscular fibres  on each  side  act,
they keep the body erect.
               INTER-TRANS VERS ALES COLLI.

  These are small muscles which fill  up the spaces between
the transverse processes  of the vertebras of the neck.   They
are distinguished  into  anterior,  six  in number on either side,
and into posterior, five in number.   The two muscles of each
interval  are  separately attached, and  extend from the inferior
border of the transverse process of the  vertebra above, to the
superior border of the transverse process of the vertebra below.
  The anterior set are connected in front with the rectus cap-
itis  anticus major; the posterior behind, with the splenius,
transversalis colli, and sacro-lumbalis.
  These muscles  contribute to the lateral motions of the neck.
             INTER-TRANSVERSALES  LUMBORUM.

   Between the transverse processes of the lumbar vertebras are
 fleshy fasciculi,  similar to those just described.  There are
 five on each side; they are stronger and more distinct than the
 preceding muscles.
   Their posterior surface  is  connected with the sacro-lumba-
 lis ; the anterior with  the quadratus lumborum.   Their lower
 and upper edges are connected with the corresponding adjacent
 transverse processes  by means of short aponeurotic fibres.
  These  muscles  are supposed  to  bend  the lumbar region of
the vertebral column laterally; the short muscles  of the spine
certainly strengthen  the back during muscular exertions. 
240
MUSCULAR SYSTEM
                    CHAP.  V.


           MUSCLES OF THE EXTREMITIES.

MUSCLES  OF  THE  SUPERIOR EXTREMITY.


            MUSCLES  OF THE SHOULDER.

               POSTERIOR SCAPULAR REGION.
SUPRA-SPINATUS.

     Fig. 145.           I
  This muscle, I, fills  up the cavity above the spine of the
scapula.   Its attachment on the inner side is fleshy, from the
whole concave surface  above k, the spine of the scapula, from
the spine, and from  the superior border  of that bone passing
under the acromion and adhering to the capsular  ligament of
the joint; on the outer part it forms a strong tendon, which is
inserted into the greater tuberosity of the humerus. 
OF THE  SUPERIOR EXTREMITY.        241
  The posterior surface of this muscle is connected with the
trapezius, deltoides, and coraco-acromial ligament;  the anterior
with the fossa supra-spinata, the superior scapular vessels  and
nerves, and with the capsule of the shoulder joint.
  This muscle raises the arm, and if the arm  is fixed  it acts
upon the shoulder.
                      INFRA-SPINATUS.

  The  infra-spinatus,  a, b, c, d, occupies  that  space on  the
back of the scapula which is below the spine.   It is attached,
on the inner side, to the two internal  thirds of the infra-spinata
fossa ; the fibres converge towards a central tendon which runs
over the neck of the bone, adheres to  the  capsular  ligament,
and is inserted into d, the greater tuberosity of the humerus.
  The posterior surface of the infra-spinatus is connected with
the deltoides, trapezius, latissimus dorsi, and integuments ;  the
anterior surface with the  infra-spinata  fossa,  from which it is
separated, in its outer third, by cellular tissue,  and by the supe-
rior scapular nerve and vessels.  It is  also applied upon  the
capsule of the shoulder joint.   The lower  edge  is confounded
with e,/ the teres minor.
  This  muscle turns the arm outwards, and assists in raising it.
                       TERES MINOR.

  This muscle, e, / is placed along  the  inferior border of the
scapula.   A strong aponeurosis  covers this and the infra-spi-
natus ;  indeed, the two muscles in some subjects are so closely
united, as  to be with difficulty separated.   On the inner part,
it is attached to the inferior angle of the scapula,  and  to  the
third of the inferior border of that bone ;  on  the outer part it
  VOL.  T.            32 
242
MUSCULAR  SYSTEM
extends to/ the lower and back part of the tuberosity of the
humerus, where it is fixed by a strong tendon.
   The posterior surface  is connected  with the deltoides and
integuments ;  the anterior with  the  external scapular artery,
the long portion of the triceps, and the capsule of the articula-
tion of the shoulder.   Superiorly, it is connected with c, d, the
lower edge of the infra-spinatus muscle ; inferiorly, with g, h,
the teres major, from which at one part it is separated by i, the
long portion of the triceps.
   The office of the teres  minor is similar to that of the prece-
ding muscle.
                       TERES MAJOR.

   This muscle, g, h, is situated beneath the teres  minor.   On
the inner side it is attached  to  the quadrilateral surface of the
inferior border of the infra-spinata fossa, and to the lower third
of the base of the scapula.   On the outer side it is inserted by
a broad tendon into  the inner side of the bicipital groove of the
humerus.
   The posterior surface is connected with the latissimus dorsi,
the integuments, the humerus, and the long portion of the tri-
ceps ;  the anterior  with the subscapularis,  latissimus  dorsi,
coraco-brachialis and biceps, the axillary vessels and brachial
plexus of nerves.   The lower edge is covered by the integu-
ments, and with the latissimus dorsi, forms the posterior edge of
the axilla.   The upper edge is united to the teres minor, from
which at one part it is separated  by the long portion  of the
triceps.
   The teres major turns the arm inwards and  draws  it back-
wards. 
OF THE  SUPERIOR  EXTREMITY.        243
ANTERIOR SCAPULAR REGION.


     SUBSCAPULARIS.
Fig. 146.
  This is'a very thick triangular muscle, a, occupying the whole
of the subscapular fossa.  It is attached on the inner side to the
internal three fourths of the  subscapular  fossa ; the fibres are
disposed in fleshy bundles with aponeurotic septa, which, con- 
244
MUSCULAR  SYSTEM
verging, slide over the inner surface of the neck of the scapula,
and pass under i, the coracoid process;  it then forms a broad
and flat tendon which adheres to the capsule of the joint, and
is finally fixed  at c, to the small  tuberosity of the humerus.
  The anterior surface of the subscapularis is connected by a
thick  layer of cellular tissue with the serratus magnus, the bra-
chial  plexus of nerves, the axillary artery, and the coraco-
brachialis, the biceps  and the deltoid muscles;  the posterior
surface with the subscapular  fossa, and  with the teres major,
the long portion  of  the triceps extensor  cubiti, and with the
capsule of the articulation of the shoulder.
  When the arm is distant from the body it draws it near;  or
it turns the arm inwards ; or when raised depresses it.

                  EXTERNAL SCAPULAR REGION.

                        DELTOIDES.*

                           Fig. 147.
* So named from its resemblance to the Greek letter J. 
            OF THE  SUPERIOR EXTREMITY.         245

  The deltoides  forms  the fleshy part  of the shoulder; its
shape and the direction of its fibres are exhibited in the figure.
Superiorly it is attached by aponeurotic fibres at a, to the exter-
nal third  of  the clavicle;  at b, to the acromion process ;  and
at c, to the lower margin of the spine of the scapula ; inferiorly
the fibres concentrate to a  tendon which  is inserted at d, into
the deltoid impression in the middle part of the external surface
of the humerus.   This muscle is composed of large fasciculi of
fibres separated by grooves more or less deep.   The inner sur-
face is aponeurotic ; and where it lies over the greater tuberos-
ity of the  os humeri, there is a bursa of considerable size.
  The external surface of  the  deltoides is connected with  the
platysma  myoides, and  the  integuments ;  the internal with  the
infra-spinatus,  teres minor, and triceps extensor muscles,  the
tendon of the  supra-spinatus, the  acromio-coracoid ligament,
the subscapularis, pectoralis minor, biceps  and coraco-brachialis
muscles, the coracoid process, the capsule of articulation,  the
superior third of the external surface of the humerus, and tendon
of the pectoralis major.   The anterior part, which is parallel
to the external border of the biceps, is separated from the pec-
toralis major by the cephalic vein.
  The principal office of this muscle  is to raise the arm ;  but
it is also  capable of moving it  forwards or backwards, accord-
ing as the anterior or posterior fibres are brought into action. 
246
MUSCULAR  SYSTEM
MUSCLES   OF  THE  ARM




   ANTERIOR BRACHIAL REGION.




      CORACO-BRACHIALIS.




            Fig. 148.
 
OF THE UPPER  EXTREMITY.          247
  We see the  situation of this muscle, a, in the figure;  it is
long, flat, and narrow.   It is attached by a tendon at a, to the
apex of  b, the  coracoid process of the  scapula; it terminates
tendinous about c, the middle of the humerus, and is  inserted
into a rough elevated line.
  The anterior surface  is connected with the deltoides, pecto-
ralis  major, and biceps ; the posterior  with  the  subscapularis
muscle, the united  tendons of  the  latissimus dorsi and teres
major, the axillary artery,  the musculo-cutaneous and median
nerves, and the brachial artery.
  This muscle  moves the arm forwards,  upwards, and inwards.
  The coraco-brachialis is perforated by a nerve called muscu-
lo-cutaneous. The intermuscular aponeurosis is seen extending
from the  lower part of this muscle along a ridge to the internal
condyle,  separating the brachialis internus from the third head
of the triceps.


                  BICEPS FLEXOR CUBITI.

  This muscle, Fig. 146,  k, is situated at the front and inner
part of the arm ; it is thick at. its middle portion, thin at its ex-
tremities, the superior of which  is divided into  two  portions.
Its short  portion is attached at A, to the coracoid process of the
scapula,  along with m, the preceding muscle, and by g, its long
portion, to the superior  part of  the glenoid  cavity; at k,  the
two portions or heads form a thick mass, and about the middle
of the arm become inseparably united ;  it  is finally inserted at
its inferior extremity to  /, the tubercle at the upper end of the
radius, and by a tendinous  expansion into  the aponeurosis of
the fore  arm.
  The anterior surface  of this  muscle, is connected with the
deltoid and  great  pectoral muscles, the  brachial aponeurosis,
and the integuments ; the posterior with the humerus a, Fig.
148, the  coraco-brachialis d, e,  the brachialis  internus, and the 
248
MUSCULAR  SYSTEM
musculo-cutaneous nerve; on the inner side with the coraco-
brachialis above, and in the middle and below with  the bra-
chial artery.
   The biceps flexor cubiti bends the fore-arm on the arm, and
the arm on the shoulder.

                   BRACHIALIS INTERNUS.

   This muscle, d,  e, is  situated at the anterior and inferior
part of the arm.  At  its  upper extremity, d, it is attached on
each side of the  insertion of the deltoides, to the external and
internal surface of c, the humerus, and to most of the lower and
fore part of the  bone, as far  as the articulation of the elbow
joint;  it has also an  attachment to the external  and internal
aponeurosis,  and inferiorly, by a  strong  tendon at e, to the
rough surface  immediately below the coronoid process of the
ulna.  The fibres pass over  the joint, and adhere to the cap-
sular ligament.
   The anterior surface of this muscle is  connected with the
brachial  aponeurosis and  the  integuments, the supinator radii
longus, the  biceps, the musculo-cutaneous nerve,  the brachial
artery, the median  nerve, and the pronator teres ; the posterior
surface with the inferior part of the humerus and  the articula-
tion of the elbow.
   The brachialis internus bends the fore-arm.

                 TRICEPS EXTENSOR CUBITI.

   The triceps, / g, h, i, occupies  all the  posterior  part of the
arm.  It is very thick  and fleshy, and is divided at the up-
per part into  three portions, whence it derives its name.   Of
these, the first or middle, which is longer and larger than the
others, is attached by a broad tendon /  to the inferior border of
the scapula, near its  neck; it then forms a large fleshy mass,
which covers the back of the os humeri.   The second or outer 
               OF  THE UPPER  EXTREMITY.          249

portion, g, is attached by a pointed extremity to  the outer and
back part of the os humeri, below the great tuberosity, and to a
ridge which runs from that eminence to the  outer condyle, and
to the intermuscular aponeurosis, which is common to  it  and
the brachialis internus.   The third or inner  portion, h, which
is the shortest, commences  by an acute form from the inner edge
of the os humeri near its middle,  and receives an  addition of
fibres  from  the  intermuscular partition ; its fleshy fasciculi de-
scend backwards and outwards.   The three portions of this mus-
cle unite about the middle of the humerus,  invest the whole
back part of the bone, and  terminate by a very strong,  broad,
and thick tendon, which is  inserted into the  upper part of the
olecranon.
  The posterior surface of the  triceps extensor is connected
above with the deltoides and teres minor, the brachial aponeu-
rosis and integuments.   The anterior surface is connected with
the subscapularis, teres  major, and latissimus dorsi, the capsule
of the articulation of the shoulder, and the posterior part of the
elbow joint.
  The triceps extensor, by extending the fore-arm, acts  in op-
position to the biceps flexor.   The long portion has the power
of carrying the arm backwards.
VOL. I.
33 
250
MUSCULAR  SYSTEM
          MUSCLES  OF  THE  FORE-ARM.

              ANTERIOR REGION OF THE FORE-ARM.

                    PRONATOR  TERES.

  This muscle, a, is extended obliquely across the  upper  and
      Fig. U9.            anterior part of the  fore-arm.   See
                        also Fig. 150, a, b, c, and Fig.  153,
                        a, b.  Superiorly it is attached to the
                        anterior part of the inner  condyle of
                        the humerus, and to the inner side of
                        the coronoid process of the ulna ; be-
                        tween  these  two  parts  the  median
                        nerve passes.  Inferiorly it is fixed to
                        the middle part of  the  external  sur-
                        face of the radius.
                          The anterior surface of  this mus-
                        cle is connected with the  aponeurosis
                        of the fore-arm and integuments, the
                        supinator radii longus, the radial  ves-
                        sels and  nerves,  and  the  external
                        radial muscles ; the posterior surface
                        with the brachialis  internus,  the flexor
                        sublimis, the median nerve,  and the
                        ulnar artery ; on the inner side  with
                        the triangular space  for  the  tendon
                        of the biceps, the brachial artery, the
                        median  nerve, and the supinator radii
                        brevis.
                           The pronator teres turns the radius
and hand inwards, or it may  assist as a flexor of the  fore-arm.
 
OF  THE  UPPER EXTREMITY.          251
                  FLEXOR CARPI  RADIALIS.

   This muscle, b, is situated on the inner side of the preceding.
It has  a tendinous attachment to the fore part of the inner con-
dyle of the humerus, fleshy to the fascia  and intermuscular
aponeurosis, and to the upper end  of the ulna.   The  extent of
its muscular fibres is marked in the figure.   The tendon of this
muscle passes under the annular ligament of the wrist, through
a groove in the trapezium, and is fixed to the base of the meta-
carpal  bone which sustains the  fore-finger.
   The anterior surface of the flexor carpi radialis is connected
externally with a, the pronator teres, and with the aponeurosis
of the fore-arm ; the posterior surface with the flexor digitorum
perforatus,  the flexor longus pollicis muscles, and the wrist.
   This muscle bends the wrist, turning it a  little inwards.   It
also serves  as a flexor of the fore-arm.
                     PALMARIS LONGUS.

   This muscle, c, d, is not always to be found in the arm.   It
 has a  slender  form,  and  is  attached superiorly  by tendinous
 fibres to the inner condyle of the  os humeri; it then forms,  at
 c, a thin fleshy mass, which, about the middle of the arm, sends
 off a small tendon which is inferiorly adherent to the annular liga-
 ment, and is spread out into a very strong tendinous membrane,
 d, named the palmar aponeurosis, which is finally fixed to the
 roots of all the fingers.
   The anterior surface is connected with the aponeurosis  of
 the fore-arm ;  the posterior  surface with the superficial flexor
 of the fingers.
  The palmaris binds down the muscles of the palm of the hand,
and its aponeurosis protects the blood-vessels and nerves  in their
course to the fingers. 
252
MUSCULAR  SYSTEM
                  FLEXOR CARPI  ULNARIS.

   The flexor carpi ulnaris, e, is situated internally to the pre-
ceding muscles of the fore-arm.   It is  half-penniform, and  is
attached by means of a common tendon to the inner side of the
olecranon, and to the posterior  border of the ulna ;  a number
of its fibres are also united to the aponeurosis of the  fore-arm.
Inferiorly it becomes tendinous, and is inserted into the pisiform
bone, and some  fibres are detached from it to the annular liga-
ment of the wrist.
   The anterior  surface of this muscle  is connected  with the
aponeurosis  of the fore-arm; the posterior surface with the
deep flexor of the fingers,  the ulnar artery and nerve,  and the
pronator quadratus, and on the outer edge with the flexor sub-
limis.
   This muscle bends the wrist, inclining it a little towards the
ulna.  When  it  contracts  at the same  time  with the  flexor
carpi radialis, it draws the hand directly upwards. 
OF  THE  UPPER  EXTREMITY.
253
FLEXOR  DIGITORUM SUBLIMIS VEL PERFORATUS.
   This muscle, d, e, is situated immediately beneath  the pre-
                           ceding  muscles.   It is attached
                           superiorly at d, to the inner con-
                           dyle of the humerus; at b, to the
                           coronoid process of the ulna;  and
                           at c, to the upper  part  of  the an-
                           terior border of the  radius; these
                           several attachments  as they  de-
                           scend form  a strong  fleshy mass,
                           which sends off four tendons ;  the
                           tendons are connected by cellular
                           tissue, and pass under the annular
                           ligament of the wrist; from thence
                           diverging as they proceed towards
                           their respective fingers,  each ten-
                           don, as it were, splits  at the ex-
                           tremity of the first phalanx for the
                           passage of the flexor  profundus,
                           and  is  attached   to  the  second
                           phalanx.
                             In this figure the fibrous sheaths
                           of the fingers are pinned open ;
                           and in the  fore finger, at g, we
                           observe the splitting of the tendon
                           just mentioned.
                             The anterior surface  of this
                           muscle is connected with the pro-
nator teres, the flexor carpi radialis, the  palmaris longus,  the
aponeurosis  of the fore-arm, the annular ligament, the palmar
aponeurosis, the fibrous sheaths of the  fingers, and with  the
tendons of the deep flexor.  The posterior surface is  connected
 
254
MUSCULAR SYSTEM
with the flexor profundus, the flexor longus pollicis, the median
nerve, the ulnar artery,  the lumbricales muscles, and the pha-
langes.
   This muscle bends the second joint or  phalanx  upon the
first, and the hand upon  the fore-arm.
Fig. 151.
  a, Tendon of  the flexor  sublimis ;  b, the division  or  slit in
the tendon for the passage of c, the tendon of the flexor profun-
dus, to be attached at e, the extremity of the finger. 
OF  THE  UPPER  EXTREMITY.          255
ANTERIOR DEEP REGION OF THE FORE-ARM.
      FLEXOR DIGITORUM PROFUNDUS  VEL PERFORANS.

   This  muscle  is situated  beneath the preceding; superiorly
                            it  is attached, at a, to the  three
                            superior  fourths  of the  anterior
                            and  internal surfaces of the ulna,
                            and at b, to the  interosseous liga-
                            ment;  the  muscular fibres  then
                            form a thick mass upon the  fore
                            part of the ulna,  and divide  into
                            four portions, each of which is ter-
                            minated by a tendon. These ten-
                            dons pass under the annular liga-
                            ment of the wrist,  and perforate
                            the slits or fissures  in  the  flexor
                            sublimis, as  in  Fig. 150,  and at
                            length  are inserted  into the ante-
                            rior part of the third phalanx of
                            the fingers.  Figure 151 best ex-
                            plains  the  mode   in which  the
                            tendon  of the  flexor sublimis, a,
                            divides  at b, to transmit  the ten-
                            don of  the flexor profundus, c, e.
                              The  anterior  surface  of  the
                            flexor profundus is connected with
                            the flexor sublimis and flexor carpi
                            ulnaris  muscles, the  median and
                            ulnar nerves, and the ulnar artery;
                            the posterior surface with the fore
and inner surfaces of the ulna, the  interosseous  ligament, the
pronator  quadratus, the  anterior  radio-carpal ligaments, the
fore part of the metacarpus, the flexor brevis and  adductor pol-
licis, and the two last palmar interosseous muscles.
 
256
MUSCULAR  SYSTEM
  This muscle bends the third, or extreme joint of the fingers,
and assists  generally in the flexion  of the fingers, hand, and
wrist.
             FLEXOR LONGUS  POLLICIS  MANUS.

   This muscle, Fig. 150, f,h, Fig. 152, c, lies on the outer
side of  the  flexor profundus; superiorly it  is attached by
fleshy fibres to the fore part of the radius and interosseous liga-
ment, and has frequently a  tendon from  the inner condyle of
the humerus.   The fibres, / pass obliquely  into a tendon on
the anterior part of the  muscle ;  this  tendon passes under the
annular ligament of the wrist, runs between the two portions of
the short flexors of the  thumb, and is attached  inferiorly at. h,
the last joint.
   The anterior surface of the long flexor of the thumb is con-
nected with the flexor digitorum sublimis, flexor carpi radialis,
and supinator longus muscles, the radial artery, and the anterior
annular ligament  of the wrist; the posterior surface with the
radius, part of the interosseous ligament, the pronator quadratus,
the fore part of the carpus, and the flexor brevis pollicis.   The
inner edge lies  upon the flexor digitorum  profundus.
   The action of this muscle bends the last joint of the thumb
upon the first, the first upon the corresponding metacarpal bone,
and the latter upon the carpus ; it likewise assists in the flexion
of the fore-arm. 
OF  THE  UPPER  EXTREMITY.          257
PRONATOR QUADRATUS.
M
This muscle, c,  d,  d, as its name implies, is of a quadri-
     Fig. 153.             lateral form, and lies close to the
                         bone on  the  lower part of  the
                         fore-arm.   It is attached broad, by
                         tendinous and fleshy fibres, on the
                         inner side at  c, to the anterior sur-
                         face of  the ulna,  extending  from
                         the lower extremity  of that  bone
                         two inches  up its  edge.   The
           W%&           fibres passing nearly transversely,
                         adhere  to the interosseous  liga-
                         ment, and on the outer side at d,
                         d, are attached to the anterior sur-
                         face of the radius.
                           The  anterior  surface  of  this
                         muscle is  connected  with the flex-
                         or profundus, flexor longus pollicis
                         manus, flexor carpi radialis, flexor
                         carpi ulnaris, and with  the radial
                         and ulnar arteries;  posteriorly,
                         with the  two bones  of the  fore-
                         arm and the lower part of  the  in-
                         terosseous ligament.
                           This  muscle turns the radius
                         together with the hand inwards.
^
VOL. I.
34 
258
MUSCULAR  SYSTEM
POSTERIOR SUPERFICIAL REGION OF THE FORE-ARM.
EXTENSOR DIGITORUM  COMMUNIS.
This muscle, / is situated at  the  posterior part of the arm.
It  is attached  superiorly to the
lower part of the outer condyle of
the humerus, to the aponeurosis of
the fore-arm, and to the aponeuro-
tic septa of the different muscles in
that region.  From these several
attachments it descends vertically,
and at  the middle  of the fore-arm
the fleshy mass forms four tendons,
which pass under  g,  the annular
ligament of the wrist.   Below the
ligament the tendons  diverge, be-
come broader, and  proceed  to the
lower extremities  of the metacar-
pal  bones ; they sometimes send
aponeurotic  bands, more or less
oblique, to each other, as in the
figure before us.   These tendons
terminate on the  back of the fin-
gers by an aponeurotic expansion,
reaching to the last phalanx.
   The posterior surface of the
common extensor of the fingers  is
connected with the aponeurosis  of
the  fore-arm ;  the anterior sur-
face with the supinator brevis, ex-
tensores pollicis,  extensor indicis,
the wrist, the metacarpus, the fin-
gers, and the interossei dorsales.
Fig. 154.
m
S9* 
OF  THE  UPPER EXTREMITY.          259
  This muscle opens the hand,  and bends it  back upon the
fore-arm.
            EXTENSOR  PROPRIUS MINIMI  DIGITI.

  This muscle, h, which is placed on the inner side of the pre-
ceding, is of a very slender form.   It is attached superiorly to the
external condyle of the  humerus, and to the aponeurotic septa
which  separate it from  the  extensor communis  and extensor
ulnaris ; and its muscular  fibres, at/ constitute  one mass with
these muscles.   Within a short  distance of the wrist its fibres
pass into a tendon, which  is  transmitted through  a distinct ring
at g, in the  annular ligament, and arrives at  the posterior sur-
face of the little  finger, to which it is attached in  the same man-
ner as  the tendons of the extensor communis.
  The posterior surface of this muscle  is  connected with the
aponeurosis of the fore-arm,  and at the back  of  the hand with
the integuments.   The  anterior surface with the supinator bre-
vis, extensores pollicis, and extensor indicis.  The  outer edge
is united to the extensor digitorum communis; the  inner edge
to the  extensor carpi ulnaris.
  This muscle extends the little finger, and assists in bending
back the hand.
                EXTENSOR CARPI ULNARIS.

  This muscle, i, is situated on the posterior part of the arm ;
its shape is exhibited in the figure.  It is attached superiorly to
the lower part of the outer condyle of the humerus, to the in-
termuscular septa and aponeurosis of the fore-arm, and  nearly
the middle third of the posterior border of the ulna.  It termi- 
260
MUSCULAR  SYSTEM
nates in a strong tendon,  which is inserted into the upper  part
of the metacarpal bone of the little finger.
   The posterior surface of this muscle is  connected with  the
aponeurosis of the fore-arm,  to  which it adheres  above;  the
anterior surface with the supinator  brevis, the extensor ossis
metacarpi and extensor secundi  internodii  pollicis, and exten-
sor proprius indicis muscles, and upon the ulna.  Its outer edge
with the former  muscle ; the inner edge  with the anconeus.
                         ANCONEUS.

   This muscle, Fig,  154, /, Fig.  J 54*, a, which is situated at
the outer side of the  olecranon, consists of  a triangular fleshy
mass adhering to the capsular ligament.   It is attached superior-
ly to the external condyle of the humerus by a distinct tendon ;
inferiorly to the superior third  of the  external border and  sur-
face of the ulna.
   The posterior surface of the anconeus is  connected with the
aponeurosis of the fore-arm ; the anterior surface with  the or-
bicular ligament of the  radius, the supinator radii brevis, and
with the ulna.
   The  office of this muscle is to assist in extending the fore-
arm. 
OF THE  UPPER EXTREMITY.          261
POSTERIOR DEEP REGION OF THE FORE-ARM.
EXTENSOR OSSIS  METACARPI  POLLICIS.
This muscle, b, is placed  obliquely  at  the back and  outer
<
part of the fore-arm. It is attached
superiorly, by a pointed  extremity
to  the posterior  surface  of the
ulna, to the interosseous ligament,
and to the posterior surface of the
radius below the attachment of the
supinator radii brevis.   The fleshy
fibres terminate in  a tendon, pass-
ing along a  groove on  the outer
edge  of the lower extremity  of
the radius, and  is attached inferi-
orly to  the superior  part of the
metacarpal bone of the thumb.
   The  posterior  surface  of this
muscle is connected with  the su-
pinator radii brevis, extensor carpi
ulnaris, extensor minimi  digiti, ex-
tensor  digitorum  communis, and
extensor secundi  internodii  polli-
cis ; at the  lowest part it is in ap-
position with the aponeurosis of the
fore-arm.   The anterior surface
is connected with  a portion of the
ulna above; crossing  the  interos-
seous ligament and the posterior
surface of the radius in the middle,  and  lying  upon the  outer
surface of the radius, the tendons of the radial extensors, the
radial artery, and  the wrist below. 
262
MUSCULAR  SYSTEM
  This muscle extends the metacarpal bone of the thumb out-
wardly.  It is therefore called by some anatomists abductor
longus pollicis manus.
       EXTENSOR  PRIMI INTERNODII  POLLICIS MANUS.

   This muscle, c, is much shorter than the preceding, but of a
similar form, and is situated  immediately below it.   It is  at-
tached superiorly by fleshy fibres to  the back part of the ulna
below its middle, to the interosseous ligament and radius.   Its
tendon follows the same  direction as that of  the  extensor ossis
metacarpi pollicis ; inferiorly it is attached to the  back of the
first bone of the thumb, and its tendon  is also continued into the
second or extreme joint.
   The posterior surface of this muscle is  connected  with the
extensor secundi internodii pollicis,  extensor  minimi  digiti  and
extensor digitorum communis ; at its lowest part with the apon-
eurosis of the fore-arm.   The  anterior surface has the same
connexions as the preceding muscle, excepting  at its inferior
extremity, where it is placed  upon the first  articulation of the
thumb.
   This muscle extends the first joint of the thumb obliquely
outwards.
     EXTENSOR  SECUNDI INTERNODII POLLICIS MANUS.

  This muscle is situated below the two last.  It is attached,
tendinous and fleshy, to the posterior surface of  the ulna, and
to the interosseous ligament; its muscular fibres terminate in  a
tendon which passes in a distinct groove at the back of the ra-
dius.  It is seen to join the tendon of the extensor primi  inter- 
              OF  THE UPPER  EXTREMITY.          263

nodii pollicis, and is inserted into the back part of the last,  or
extreme joint of the thumb.*
  The posterior surface of this  muscle is connected with the
extensor carpi ulnaris,  the extensor digitorum communis and
the extensor indicis, and at its lowest part with the integuments:
the anterior surface with  the extensor ossis metacarpi pollicis
and extensor primi internodii pollicis, the bones of the fore-arm,
the tendons of the radial  extensors, the first  metacarpal bone,
and the phalanges of the thumb.
  This muscle extends the last joint of the thumb, and it may
be observed that  the  extensors just described have also the
power of carrying the hand outwards and backwards.
                        INDICATOR.

   This muscle4, d, is placed nearer to the inner edge of the arm
 than the extensors of the thumb.  It is attached superiorly  to
 the back part of the ulna, and to the interosseous ligament.   Its
 tendon passes through the same sheath of the annular ligament
 as those of the extensor digitorum communis ; and terminates  at
 the back of the fore finger with the tendon of the common ex-
 tensor.
   The posterior surface is  connected with the  extensor carpi
 ulnaris, the extensor proprius  minimi digiti, and the extensor
 digitorum communis ; the anterior surface with the  ulna, the
 interosseous ligament, the extensor secundi internodii pollicis,
 the inferior extremity of the  radius, and the back of the hand.
   The office of this muscle is to point the fore-finger,  from
 which it takes its name,

  * No letter happens to mark this muscle, although it is distinctly drawn
in Fig. 154",and placed between the points of c, and d. 
264
MUSCULAR  SYSTEM
                      RADIAL REGION.

                SUPINATOR  RADII LONGUS.

  This muscle, Fig. 149,  g, is attached by  short  tendinous
fibres to the external condyle  of the humerus, whence  it passes
downwards fleshy as far as  the middle  of the  radius  where it
terminates in a tendon, which runs along the outer edge of the
radius and is  inserted near the base of the  styloid process of
that bone.
  Its action is to roll the radius outwards, and consequently the
palm of the hand upwards.


                SUPINATOR  RADII BREVIS.

  This muscle, which is  seen in Fig. 153, e, arises  tendinous
from the external condyle of the humerus, both tendinous and
fleshy from the external and upper part of the ulna, and adheres
firmly to the ligaments that join these two bones, and is inserted
into the head, neck and tubercle of the radius.
  Its use is to roll  the radius  outwards and thus to supinate the
hand.


EXTENSOR  CARPI  RADIALIS  LONGIOR, OR   RADIALIS EXTER-
                       NUS  LONGIOR.

  This muscle, Fig. 154, b, arises from the inferior part of the
external edge of the humerus  and superior part of its external
condyle,  and  is inserted into the posterior part of the  upper ex-
tremity of the second metacarpal bone.
  It extends  the wrist and  hand,  and  abducts them a little.
Acting with the extensor carpi ulnaris, it  extends  the  hand
directly.   Acting with the  flexor carpi radialis, it produces the 
OF THE  SUPERIOR  EXTREMITY.        265
direct abduction of the hand.   If the hand be fixed,  it extends
the fore-arm upon the wrist.

EXTENSOR CARPI RADIALIS BREVIOR,  OR  RADIALIS  EXTER-
                       NUS BREVIOR.

   This muscle is precisely similar to the  preceding,  behind
which it is placed.  It arises from the external condyle of the
humerus and is inserted in the  posterior part of  the  upper ex-
tremity of the third metacarpal bone.
   It assists the former.


              MUSCLES OF  THE HAND.

                   EXTERNAL PALMAR REGION.
           ABDUCTOR  BREVIS  POLLICIS  MANUS.

  This muscle, b, c, constitutes the outermost  portion  of the
       Fig. 154.                    ball of the thumb.   It is at-
                                  tached  at b, to the anterior
                                  surface  of the annular  liga-
                                  ment of the wrist, and to the
                                  os scaphoides and os trape-
                                  zium ;  from  thence  it de-
                                  scends a little obliquely out-
                                  wards.   Its  fibres converge
                                  towards each other, and are
                                  attached by  a tendon at c,
                                  to the outer side of the ex-
                                  tremity of the first phalanx
                                  of the thumb.  In this  fig-
                                  ure  the muscle is  divided
                                  and turned back.*
  * Sometimes this forms two muscles, designated abductores breves pollicis
manus, interior el exterior.
  vol.  i.               35
 
266
MUSCULAR  SYSTEM
    The anterior surface is connected with the palmar aponeu-
 rosis  and the integuments ;  the posterior surface with  the
 opponens and flexor brevis pollicis manus.
    The office of the abductor pollicis is  to carry the thumb from
 the fingers.

                     OPPONENS POLLICIS.
    This muscle, d, lies under the preceding.   It is attached su-
 periorly by aponeurotic fibres to  the annular  ligament  of  the
 wrist, to  the os naviculare and the os trapezium.  Inferiorly to
 the anterior  and lower part of the metacarpal bone  of  the
 thumb.
    The anterior surface of this muscle is  covered by  the pre-
 ceding and by the integuments ;  the posterior surface is con-
 nected with  the anterior  annular ligament  of the carpus, the
 articulation of the trapezium at the first metacarpal bone, part
 of the anterior surface of that bone, and the flexor brevis polli-
 cis manus.
   The office of this muscle is to bring the thumb inwards, so
 as  to oppose the fingers, from which circumstance it has derived
 its name.

             FLEXOR BREVIS POLLICIS MANUS.

   This muscle, Fig. 156, e, is of a short, thick, triangular form,
 and is placed  beneath the two preceding.   It is attached supe-
 riorly to the under part of the annular ligament of the carpus,
 to the  os magnum, and to the third metacarpal bone ;  inferior-
 ly it is inserted into the sesamoid bone, which is connected by
 a ligament to the fore part of the upper extremity of the first
joint of the thumb.
   The anterior surface of this  muscle  is  connected with the
tendon  of the flexor brevis pollicis  manus,  the tendons of the
flexor profundus digitorum, the two  first lumbricales, with an
aponeurosis, the integuments, and the adductor minimi digiti; 
OF  THE  SUPERIOR  EXTREMITY.        267
the posterior surface with the first metacarpal bone,  the first
two dorsal and the first palmar interosseous muscles, and  the
tendon of the flexor carpi radialis.
  This muscle  bends the  first phalanx of the thumb, and  the
whole thumb towards the wrist.
                ADDUCTOR POLLICIS  MANUS.

   This muscle, c, which is broad, thin, and triangular, is  still
           Fig. 156.               more deeply seated than the
                                 flexor brevis.  On the inner
                                 side it is  attached  to nearly
                                 the whole length of the  me-
                                 tacarpal bone of the middle
                                 finger, and crossing the  me-
                                 tacarpal  bone of the fore-
                                 finger,  its  fibres  converge,
                                 and are outwardly  inserted
                                 by a tendon with e, the pre-
                                 ceding muscle, into the inner
                                 and  upper  part  of the  first
                                 bone of the  thumb.
                                   The  anterior  surface is
                                 connected with the tendons
of the flexor profundus, the two first  lumbricales, and  with  the
integuments ; the posterior with  the interossei and the bones
of the metacarpus.
  This muscle draws the thumb towards the fingers.
INTERNAL PALMAR REGION.
PALMARIS BREVIS.
  The palmaris brevis is not easily demonstrated in every sub-
ject, for it consists merely of several small fasciculi of muscular
fibres, situated immediately under the skin of the palm of the 
268
MUSCULAR  SYSTEM
hand.  On the outer side it is attached to the annular ligament
of the wrist, and to the palmar aponeurosis ; on  the inner side
to the chorion of the skin which covers the little finger and in-
ner edge of the hand.
   The anterior surface of this muscle  is connected with  the
integuments;  the posterior surface  with the  abductor and
flexor muscles of the little finger, the ulnar artery and the nerve.
   The office of these fibres is to contract the  skin of the palm
of the hand.

                 ABDUCTOR MINIMI  DIGITI.

   This muscle, Fig. 155,/, is placed on the  inner edge of the
palm of the hand.   It is attached superiorly to the os pisiforme,
and to the adjacent annular ligament  of the  carpus ; its fibres
extend along the metacarpal bone of the little finger, terminating
in a tendinous attachment to the inner side of the fi.st phalanx
of that finger, and in the  aponeurotic  expansion which covers
the back part of the same finger.
   The anterior surface of the abductor of the  little finger is
connected with the preceding muscle,  a  very thin aponeurosis,
and with the integuments ; the posterior surface with the  ad-
ductor ossis metacarpi minimi digiti.
   The action of this muscle draws the little finger inwards and
forwards, and separates it from the other fingers.


             FLEXOR PROPRIUS MINIMI DIGITI.

   This muscle, Fig. 155, g, is situated  by the side of the pre-
ceding.   It  extends from the os cuneiforme, and from the annu-
lar ligament of the carpus to the upper portion of the first pha-
lanx of the little finger, to which it is attached  with the pre-
ceding muscle by a round tendon ; its connexions are the same
as the preceding muscle. 
OFTHE  SUPERIOR  EXTREMITY.        269
   This muscle ^nds the first joint of the little finger, and assists
the adductor.  '•

        ADDUCpR OSSIS  METACARPI  MINIMI  DIGITI.*

   This muscle,Fig.  156, a, is almost concealed by the two
muscles last dgcribed.   It is  attached superiorly,  by fleshy
fibres, to the osunciforme and annular ligament of the  carpus ;
it forms a thickmass, which  is attached inferiorly by a tendon
to the fore part )f the metacarpal bone of the little finger.
   The  posterior turface is connected with the last interosseous
muscle, the fourth metacarpal bone, and the tendon of the flexor
sublimis, which passes to  the little finger.
   This muscle carries the metacarpal bone  of the little finger
outwards, and assists the flexor.

                    MIDDLE PALMAR REGION.

                       LUMBRICALES.f

   The  lumbricales are four small muscles, Fig. 155,  a, a, a, a,
situated in the palm of the hand.   They are attached superiorly
to the tendons of the flexor digitorum profundus perforans; each
muscle  has a tendon, which passes along the side of the finger,
and is attached inferiorly  to the back part of the first joint.
   The  anterior surface is connected with  the tendons of  the
flexor digitorum profundus, the palmar aponeurosis, and the col-
lateral vessels and nerves  of the fingers ; the  posterior surface
with the interosseous muscles, the  inferior transverse  metacar-
pal ligament, and the phalanges.
   These muscles bend the first  phalanx: they are  small and

  * This muscle is frequently designated opponens minimi digiti.
  t These derive their name from their resemblance to the lumbricus or
earth-worm. 
270
MUSCULAR  SYSTEM
appear insignificant as flexors, when comparecwith the power-
ful muscles already described, but they are indipensably neces-
sary in the performance of the rapid  movemets of the fingers,
as in playing on musical  instruments, etc.   lence Cowper
gave them the name  of musculi fidicinales.

                       interossei.

  These are seven little muscles named interosei, situated  in
the intervals of the metacarpal bones ;  four, Fig. 157, a, a, a, a,
on the back of the hand, and three, Fig. 158, a, b,  d,  in the
palm : the latter are not seen till the other muscles of the thumb
and fingers are removed ;  they are designated  adductors, and
abductors, according to their uses.

                    1. ABBUCTOR INDICIS.
               Fig. 157.             Fig. 158.
  This muscle, c, Figs. 157 and 158, is of a triangular form ;
it is attached to the outer edge of  the metacarpal bone of the 
OF  HE  SUPERIOR EXTREMITY.        271
 fore-finger, and to he upper part of the inner edge of the meta-
 carpal bone of th thumb.  The  two fasciculi unite into  a
 tendon, which teninates on the outer side of the upper extrem-
 ity of the first phainx. and  the  extensor tendon  of the fore-
 finger.
    The posterior srface of this muscle is connected  with the
 integuments ;  the nterior with the first lumbricalis, the flexor
 brevis, b, the abdutor pollicis,  and the integuments.
    This muscle approximates the fore-finger to the thumb, and
 inclines the metacaaal bone inwards.

                    2.  ADDUCTOR INDICIS.

    This muscle, Fig 158, d, is placed in the palm of the hand ;
 it is attached superiorly to the inner side of the metacarpal bone
 of the fore-finger ;  iferiorly by a  tendon in the same manner as
 the preceding.
    The anterior surp.ce of the  adductor  indicis is connected
 with the flexor brev> and adductor pollicis; the inner surface
 corresponds with th< next muscle.
   The action of thi: muscle carries the fore-finger inwards.

                  3. ABDUCTOlt DIGITI MEDIl.

   This muscle, Fig. 157,  is seen  at the back of the hand.  It
 is attached to the inrer side of the second and third metacarpal
 bones, and terminate; by a tendon, like the preceding, which is
 attached to the outerside of the first phalanx of the middle fin-
 ger, and its  extensor endon.
   The posterior surjtce of this  muscle is connected with the
integuments, the tencbns of the extensor muscles of  the fore-
finger, and with an aioneurosis which passes from  the  second
to  the third  metacarpU bone ; the  anterior  surface  with the
flexor brevis and addictor pollicis.
  This muscle draws the middle finger outwards. 
272
MUSCULAR  SYSTEM
                  4. ADDUCTOR DIGITI MEDII.

  This muscle, Fig. 157, is  also  situated j the back of the
hand.   It is attached to the  inner side of th third and fourth
metacarpal bones, and terminates like the  ohers in a  tendon
which is inserted  into the inner side of the  pper extremity of
the first phalanx and extensor tendon of thejniddle finger.
  The posterior surface of this muscle  is  pnnected with the
integuments and tendons of the common  ^tensors of the fin-
gers.
  This muscle carries  the middle  finger tovirds the ring finger.
               5. ABDUCTOR DIGITI ANNULARIS.

  This muscle, Fig. 158, b, is placed in th palm of the hand ;
it is attached to the outer side of  the fourji metacarpal bone ;
and its tendon is  inserted into  the outer sidt of the first phalanx
and extensor tendon of the ring  finger.
  The anterior surface is connected with tie lumbricales mus-
cles and tendons of the flexor profundus.
  This muscle draws the ring  finger toware the middle finger.
                6. ADDUCTOR DIGITI ANNULARIS.

  This muscle, Fig. 157, is  situated on tie back of the hand.
It is attached to the inner side of the fouth metacarpal bone,
terminating in a tendon which is  inserted nto the inner side of
the ring finger.
  The posterior surface of this  muscle i  connected with an
aponeurosis which passes from the fourth t> the fifth metacarpal
bone, the extensor tendons of the little finger, and the integu- 
OF THE  SUPERIOR  EXTREMITY.        273
ments; the  anterior surface is concealed above by the inter-
osseous muscle of the little finger, but below  appears between
it and the preceding muscle.
  This muscle brings the ring finger towards the little finger.
                 7.  ABDUCTOR MINIMI DIGITI.

  This muscle, Fig. 158, a, is seen in  the'palm of the hand.
It is attached to the outer surface of the fifth metacarpal  bone;
its tendon is inserted into the outside of the first phalanx  and
the  extensor tendon of the little finger.
  The  anterior surface of this muscle is connected with the
adductor  ossis  minimi  digiti;  the outer surface corresponds
with the preceding muscle.
  The action of this muscle carries the little finger outwards.
THE ENVELOPING APONEUROSIS OF THE UPPER EXTREMITY.

  The muscles of the arm are  covered by  a delicate cellular
tissue, very different  from aponeurosis, and therefore is usually,
in dissections, taken  off with the  integuments.   But  on the
fore-arm we find a strong fascia or aponeurosis, investing all the
superficial  muscles.   This external aponeurosis is continued
from the intermuscular aponeurosis, which passes down to the
condyles of the humerus.  It is  attached  to the  condyles and
to the olecranon, and on the back part receives a great addition
of fibres from the tendon  of  the  triceps.  On the  fore part of
the arm it appears to be a continuation of the aponeurotic inser-
tion of the biceps, and is attached to all the muscles by septa,
or fibrous partitions.   The sheath descends  along the fore-arm,
adhering to the whole inner edge of the ulna, and arriving at the
wrist, is continued into the annular ligament.   The outer sur-
  vol.  i.               36 
274
MUSCULAR  SYSTEM
face is covered by skin, cellular tissue, adipose substance, and
by  the superficial veins, nerves, and lymphatics of the arm.   It
appears to form thin sheaths for these different organs ; it sends
also between  them, and especially  above them,  areolae  and
arches,  through  which the branches of superficial veins and
nerves pass.   The fibres have no constant direction, but  cross
each other in all directions, and leave  between them small open-
ings, which  are traversed by blood-vessels. 
OF  THE  INFERIOR EXTREMITY.        275
                      CHAP. VI.


MUSCLES  OF  THE  INFERIOR  EXTREMITY

                    KEGION OF THE HIP.

         MUSCLES OF  THE  HAUNCH  AND THIGH.

                  GLUTEUS MAXIMUS.

                        Fig. 159.
  This muscle is placed at the back part of the hip, covering
all the muscles situated  on that part.  A correct  idea of its 
276
MUSCULAR  SYSTEM
form may be had from the annexed representation.  It is attached
superiorly, at a, to the posterior crest of the ilium ;  at b, to the
posterior surface  of the sacrum ; at c,  to the border of the os
coccygis, and to the posterior surface of the  sacro-sciatic liga-
ment ; the fleshy fibres pass obliquely downwards and forwards,
forming a very broad, thick, coarse muscle ; its  fasciculi gradu-
ally converging, terminate in  a  strong  flat tendon, which is
attached inferiorly at  d, e, the upper and outer part of the linea
aspera of the femur.   A great portion of tendinous  fibres also
unite it to the aponeurosis of the thigh.
   The posterior  surface of this muscle  is covered  by an  ex-
tremely thin lamina of the fascia lata, adipose tissue, and skin.
The anterior surface is applied to the ilium,  sacrum,  and  the
os coccygis ; the  attachments  of the sacro-spinalis, the gluteus
medius, pyriformis, gemelli,  obturator internus,  and quadratus
femoris muscles ; to the sciatic nerve, the tuber ischii, the pos-
terior sacro-sciatic ligament, the  upper extremity of the biceps
semimembranosus and semitendinosus, the great  trochanter, and
to the triceps adductor muscle.
   The office of the gluteus maximus is  to extend the  thigh by
drawing  it  backwards  and somewhat outwards.   It  extends
likewise the pelvis on  the thigh in standing;  and assisted by the
other  glutei  in progression, it maintains the  equilibrium of the
body on the lower extremity, which rests on the ground. 
OF  THE  INFERIOR EXTREMITY.        277
GLUTEUS  MEDIUS.   »

     Fig.  160.
  This muscle, a, is broad, strong, and radiated ; it is situated
under the preceding, except  at  its  anterior part,  where it is
covered only by  aponeurosis.   Superiorly  it  is attached  by
fleshy fibres to b, b, the whole of the outer edge of the crista
of the ilium, and  to the dorsum  of that bone ; its  converging
fibres, a, are  collected, and terminate in a broad aponeurosis,
which is somewhat concealed in  its substance, but is converted
into a tendon, and is inferiorly inserted into the upper part of
c, the great trochanter.
  The outer surface of this muscle is connected with  the pos-
terior half of the gluteus  maximus,  and its anterior with the 
278
MUSCULAR  SYSTEM
fascia lata ;  the inner surface with the  iliac bone, the gluteus
minimus, pyramidalis, triceps extensor muscles, and the gluteal
artery.  The anterior edge is connected above with the tensor
vaginae femoris, but is separated below by an interval occupied
by a great quantity of cellular tissue and branches of the exter-
nal circumflex artery.   The posterior edge, at its upper part,
is parallel to the pyriformis muscle.
  The gluteus medius draws  the  thigh outwards and a little
backwards.  It also acts in standing and in progression.
GLUTEUS  MINIMUS.

      Fig. 161.
   This muscle, a, a, b, is smaller than  the gluteus medius and
is  entirely concealed until that muscle is  raised from its con-
nexions.   A synovial  bursa is found between  their tendons. 
OF THE  INFERIOR  EXTREMITY.         279
The gluteus minimus is attached superiorly by fleshy radiating
fibres at a, a, to the semicircular ridge of the ilium, and to the
dorsum  of that, bone below  the ridge.   Its  fasciculi  descend
and are  collected  together,  terminating  inferiorly in  a strong
tendon, which  is attached at b, to  the  anterior and superior
part of the trochanter major.
  The outer surface of the  gluteus minimus is connected in
the greater part of its extent with the preceding muscle ; pos-
teriorly with the pyriformis;  the inner surface with the ilium,
the fibrous capsule of the  articulation of the hip, the  curved
tendon of the rectus  femoris, and with a small part of  the tri-
ceps extensor cruris.
  This muscle  assists the two former muscles. 
280               MUSCULAR SYSTEM
PELVI-TROCHANTERIC REGION.


       PYRIFORMIS.


         Fig. 162.
  This, like the other small muscles of the hip, cannot be de-
monstrated till the gluteus maximus is  removed.   It  lies be-
hind and below the gluteus medius, but it is not at all covered
by it.  On the one part it is attached  at a,  by three fleshy
portions, to the concave surface of  the  sacrum, and becoming
round and tapering, it passes out of the pelvis' below the notch
of the posterior  part of the ilium, and above c, the superior
sacro-sciatic ligament; that part which passes out of the pelvis 
OF THE  INFERIOR EXTREMITY.         281
is seen in Fig.  161, at e, terminating in a round tendon, and is
inserted into the cavity at the root of b, the trochanter major.
   In the pelvis, the anterior surface is connected with the rec-
tum, the sciatic plexus, and  the hypogastric vessels.   After
leaving that cavity, it is in contact with the ilium, the  capsule
of the hip joint, and the gluteus minimus.   The posterior sur-
face is connected  with the sacrum and the gluteus maximus ;
the upper edge with  the gluteal  artery,  gluteus  medius, and
gluteus minimus ;  the lower edge with the anterior sacro-sciatic
ligament, and is separated from the superior  gemellus  by the
sciatic nerve.
   This muscle turns the thigh outwards :  in some degree it has
the power of turning the pelvis on the thigh.


                   OBTURATOR INTERNUS.

   The superior part of this muscle,  Fig. 162,  a, is situated
within the pelvis ;  it is attached by radiated fibres to more than
one-half of  the margin  of the  obturator  foramen, and  to the
inner surface of the aponeurosis which fills up that hole.  Its
fibres concentrate  into a round tendon,/ Fig.  161, which pass-
ing over the  ischium between the spine and tuber of that
bone, leaves the cavity of the pelvis, is inclosed in the sheath of
the gemelli, e,  g,  (as seen in Fig. 1G0 ;)  finally it is attached
with them at the root of c, the  great trochanter.   Where the
obturator bends there is a synovial capsule, lining the cartilagi-
nous layer of the  lesser sciatic notch, and reflected over the
tendon.
   The outer surface of the obturator internus  is connected with
the ilium, pelvis, obturator ligament, sciatic nerve, and gluteus
maximus ; the  inner surface with  the aponeurosis to which the
levator ani is attached, and with the capsule of the articulation
of the hip.
   vol.  t.            37 
282
MUSCULAR  SYSTEM
  The office of this muscle is to rotate the thigh and leg out-
wards, and to draw it in the same direction.
OBTURATOR EXTERNUS.
Fig. 163.
  This muscle covers the external obturator foramen.   It is
not distinctly seen until all the muscles which run from the pel-
vis  to the upper part of the thigh are removed.   Inwardly, it
has a fleshy attachment, at a, to the circumference of the obtu»
rator foramen, and  to the external surface of the  obturator
aponeurosis ; its fibres are directed outwards through the notch
placed between the inferior margin of the acetabulum and the
tuberosity of the ischium, pass round the cervix of the femur,
adhering to e, the capsular ligament, and terminate in a tendon
which is attached outwardly, at the root of the trochanter major, 
OF THE  INFERIOR EXTREMITY.        283
immediately below the gemelli, as seen in Fig. 160, below the
letter g.
   The  anterior surface of the obturator externus is connected
with the pectineus, the adductors, and the quadratus femoris ;
the posterior surface with the ilium, the obturator ligament, and
the capsule of the articulation of the hip.
   The  office of this muscle is to rotate the thigh  obliquely out-
wards.


                   GEMELLUS SUPERIOR.*

   This muscle, Fig. 160, e, is placed below the preceding.   It
is  short, flat, and broad, thicker in the  middle than at  the ex-
tremities.  It is attached on the inner side to the external bor-
der of the sciatic  spine,  then proceeds transversely outwards,
and embraces the tendon of/ the obturator  internus,  and be-
comes attached outwardly to the upper part of the inner surface
of the great trochanter.
   The posterior surface of the gemellus superior is connected
with the sciatic nerve and gluteus maximus ;  the anterior sur-
face with the ilium and the capsule of the articulation of the
hip.


                   GEMELLUS INFERIOR.

   ITiis  muscle, Fig. 160, g, has the same form, attachments,
and connexions, as the gemellus superior.  The two tendons of
the gemelli unite behind that of the obturator  internus,  so as to
form a kind of channel.
   These muscles roll the thigh outwards, and draw the one from
the other.

  • This muscle, and the following, are frequently designated under the gen-
eral name of musculi gemini. 
284
MUSCULAR  SYSTEM
                    QUADRATUS FEMORIS.

   This muscle, Fig. 161, is  situated below the inferior gemel-
lus.  On the inner side, it is attached, at c, to the ischium, be-
tween its tuberosity and the obturator foramen ; on the outer
side, its fibres mn  transversely, and  are attached at  the  back
part of the femur to a rough line, which extends  from the root
of the great to  that of d, the small trochanter.*
   The posterior surface of the quadratus femoris is connected
with the  sciatic  nerve,  the  gluteus  maximus, the semimem-
branosus, and the adductor magnus muscles ;  the anterior sur-
face with the obturator externus, the extremity of the tendon of
the psoas magnus, and the posterior  part of the small trochan-
ter.
   The office of this muscle is to turn the lower extremity out-
wards.
* This muscle is also shewn in Fig. 163, at b. 
OF  THE  INFERIOR EXTREMITY.         285
ANTERIOR


       S.4
This muscle, b, which is

       Fig. 164.
RAL REGION.

UUS.

!  longest of  the human body,
  is situated  on the front and
  inner part  of the thigh, be-
  fore the other muscles.   Su-
  periorly  it  is attached at h,
  to the  anterior superior spi-
  nous process  of  the ilium;
  crosses the thigh obliquely,
  passes  behind the inner con-
  dyle of the femur, at e, and
  is  inserted  inferiorly  by  a
  broad  tendon, at i, to the
  inner side of the  head of the
  tibia, near the inferior part
  of its tubercle.
    The   anterior surface  of
  the  sartorius  is  connected
  with the fascia lata ; the pos-
  terior  surface  from  above
  downwards with the  psoas
  magnus  and iliacus  internus,
  the  rectus  femoris, triceps
  extensor   cruris,   adductor
  longus,  adductor]  magnus,
  and  gracilis muscles ;  with
  the  crural   artery about  the
  middle of  the thigh ;  and at
  its lower part"witrr  the inter-
  nal  lateral  ligament  of the 
286
MUSCULAR  SYSTEM
articulation of the knee.   The inner edge of the superior part
of this  muscle forms with the adductor  longus a  triangular
space, in which  the crural artery, vein, and nerve, are situated.
   The  action of this muscle brings the leg obliquely inwards,
as when tailors cross their legs at work ; and from this circum-
stance the muscle obtains its name.   Its continued contraction
will also bend the thigh on the pelvis.
                     RECTUS  FEMORIS.

   The rectus femoris, Fig.  164,  c, is  situated immediately in
front of the  thigh ;  its fibres are penniform.  Superiorly it is
attached by a tendon to the anterior inferior spinous process of
the ilium, and by another strong tendon  to the dorsum of that
bone  a little above  the edge  of the  acetabulum, and is also
adherent to the capsular ligament of the hip joint.   These two
tendons unite and form  a  fleshy mass, which terminates  inferi-
orly in a flat tendon  at /  and is inserted into the upper part of
the patella, g, where a  thin aponeurosis is continued over that
bone, and becomes ligamentous at h, connecting the lower part
of the patella to the tibia.   Thus, virtually the rectus is attach-
ed to the large bone  of the leg.
   The anterior surface of the  rectus femoris is connected with
the fascia  lata, iliacus externus, and sartorius muscles ; the pos-
terior surface with the  articulation of the hip, the external cir-
cumflex vessels, and the triceps extensor cruris.
   The office of this  muscle  is  to extend the leg  on the thigh,
and the thigh on  the pelvis ; when standing, it assists in fixing
the body. 
OF THE  INFERIOR  EXTREMITY.        287
TRICEPS EXTENSOR
This  muscle  embraces  the
     Fig. 165.
       Vastus externus,
       Vastus internus,
       Crurceus.

femur from the  base  of the
  trochanters  to  the  patella.
  The older writers described it
  as  three distinct  muscles;
  and as its upper part  is divi-
  ded into three  fasciculi, the
  distinction is here retained.
    1st. The external fascicu-
  lus, or vastus externus.  This
  portion forms the fleshy mass
  which   occupies  the  outer
  side of the thigh bone; it is
  attached superiorly, by ten-
  dinous and fleshy fibres, at a,
  to the anterior surface of  the
  great trochanter, to the outer
  border   of  the  linea  aspera,
  and to   the oblique line run-
  ning to the external condyle.
  The fleshy  fibres  pass for-
  wards,  and are connected  at
  b,  to the tendon of the cru-
  raeus,  and  inferiorly, at c, to
  the side of the patella : part
  of  it   also  ends,  at  d,  in
•  an  aponeurosis which passes
  over the side of the  knee,  is
  fixed to the head of the tibia,
  and continued to the leg. 
288
MUSCULAR  SYSTEM
   2d. The internal fasciculus, or vastus internus, covers the
 inner part of the femur, in  the same manner as the preceding
 portion does the outer side.   It is attached by aponeurotic and
 fleshy fibres, at / to the fore part of the minor trochanter; its
 fibres are continued along the inner border of the linea aspera,
 and the oblique line running to the inner condyle, taking a di-
 rection downwards and forwards; they  are then connected, at
 b, to the tendon of the  cruraeus,  and inferiorly to the side of
 the patella, c, and to the aponeurosis of the leg.
   3d.  The  middle fasciculus  b,  is called the cruraus vel
 cruralis, the  principal  part of which   is concealed by  the
 fleshy masses of  the vasti,   and is  connected  intimately with
 them.   It is attached superiorly between the trochanters of the
 femur and to the fore part of that bone  almost to  its inferior
 extremity.   As before stated, the sides are united to the vasti
 fasciculi.  The  front  is  covered by the rectus, the tendon of
 which,  at g, joins it near the lower part  of the thigh, terminat-
 ing with it  in c, the patella.*
   The  anterior  surface of  this muscle is connected externally
 and above with  the  tendons of the  gluteus maximus and
 minimus, farther  down  with  the fascia  lata  and its  tensor
 muscles,  and  at  its lowest  part with the short portion of the
 biceps.    In  the  middle it  is  in  connexion with the external
 circumflex vessels ;  internally, the  fascia lata, the crural artery,
 and the  sartorius, are in  contact with it.   The  posterior sur-
face is connected  with  the whole surface of  the shaft  of  the
 thigh bone, but it is separated below from it by a mass of cel-
 lular and adipose  tissue.
   The office of the triceps extensor muscle is  to extend  the
 le g on the thigh, and the latter on the former.

  * There are frequently found some fasciculi of  muscular fibres under the
 middle portion, and attached to the  capsule of the knee joint, which have
 been considered by some anatomists as a separate muscle, under the name
 of subcruraus. 
OF  THE  INFERIOR  EXTREMITY.        289
INTERNAL FEMORAL REGION.
PECTINEUS.
muscle, d, is situated at the superior part of the thigh,
Fig. 166.
  and is of a flat, long, and tri-
  angular figure.   It is attached
  superiorly by aponeurotic ad-
  hesions to the brim of the pel-
  vis ;  inferiorly by means of a
  tendon to  the  linea aspera,
  immediately  below  the tro-
  chanter minor.
    The anterior surface  of the
  pectineus  is  connected  with
  the fascia lata and the crural
  vessels and nerves;  the pos-
  terior with the pubis, the ar-
  ticulation of the hip, the obtu-
 rator  externus,  the adductor
 brevis muscles, and the  obtu-
 rator vessels and nerves.  The
 inner border is a little covered
 by the adductor longus; the
 outer  is parallel  to  the  psoas
 magnus.
   The office of this muscle is
 to bend the thigh,  and to ro-
 tate it, as when  we turn  out
our  toes.   It  also bends  the
pelvis  upon the thigh, or pre-
serves  it in  its upright  posi-
tion.
k h
38 
290
MUSCULAR  SYSTEM
                         GRACILIS.

  The gracilis, which is situated on the inner side of the thigh,
is a long, thin, flat muscle.   Superiorly it is attached at a, by
an aponeurosis or  flat, thin tendon, to b, the ramus  of the os
pubis, near the symphysis ;  descending in a  direct  course by
the inside of the thigh, it  terminates at h, in  a tendon,  which
passes behind the inner condyle of the femur, and  is attached
inferiorly to the inside of the tibia below the tendon of i, the
sartorius, and  above  that of k, the semitendinosus.
  The inner  surface is connected with the fascia lata and the
sartorius ; the  outer with the  adductors, and the semimem-
branosus muscles, and the internal lateral ligament of the knee
joint.
  This muscle, like  the sartorius, brings the thigh inwards and
forwards ; it acts also as a flexor of the leg and thigh.


                ADDUCTORS OF THE THIGH.

  The adductor muscles of the thigh consist of three distinct
muscles, though they are frequently described as one  under the
name of triceps adductor femoris.


                     ADDUCTOR LONGUS.'

  This muscle, Fig. 167, is placed between the pectineus and
gracilis.   It is attached superiorly, by a  short and strong  ten-
don at b, to the upper and inner part of the os pubis, near its
symphysis ; the fibres,  a, descend obliquely, and are  inferiorly
attached by an aponeurosis at  c, to the  middle  of  the linea
aspera, occupying rather more than one third of its length.
   The anterior surface of the adductor longus is connected with 
OF  THE  INFERIOR  EXTREMITY.         291
the fascia lata, the sartorius, and the femoral  artery ; the pos-
terior surface with the two other adductor muscles, and is al-
most inseparably  united  to them below.   The outer border is
parallel to the pectineus muscle ; the inner is concealed by the
gracilis.


                    ADDUCTOR BREVIS.

   This muscle is situated behind the preceding ; it is of a  tri-
angular, flat figure, and is attached superiorly, by tendinous and
fleshy fibres, to the pubes between the symphysis and obturator
foramen ;  inferiorly, to the upper third of the linea aspera, where
its insertion is blended with the adductor  longus, the adductor
magnus, and the pectineus.
   The anterior surface of the adductor brevis is connected
with the  preceding muscle and the  pectineus ; the posterior
with the adductor magnus.  Inferiorly  it is united  to the gra-
cilis ; and externally to the tendon  of the psoas magnus, the
iliacus internus, and to the obturator externus. 
292               MUSCULAR  SYSTEM
                     ADDUCTOR

   The adductor  magnus  oc-
 cupies nearly the  whole inner
 part of the thigh ; it is situa-
 ted  behind  and   below  the
 other two adductors, and sep-
 arates the anterior and poste-
 rior parts of the thigh.  Jt is
 attached  superiorly,  at e, to
 the inferior part of the ante-
 rior surface of  the ramus  of
 the pubes ; at b, to the ante-
 rior surface of that of the ischi-
 um, and to the  external bor-
 der ofits tuberosity ; the fibres
 run inwards and downwards,
 having various degrees of ob-
 liquity, and are attached  in-
 feriorly to the whole length of
 the linea aspera, to the oblique
ridge above the  internal con-
dyle of the os femoris, and by a
long round tendon  to the up-
per part of the condyle, where
the tendon is united to the ad-
ductor longus.  There is  a
perforation in  the  tendon  of
this muscle at i, near the bone,
through which the femoral ar-
tery|passes in  its course towards
  The anterior  surface of this \
us.

       Fig. 167.
ham.
cle is  connected with the 
             OF  THE INFERIOR  EXTREMITY.        293

two  preceding, the sartorius, and the femoral artery ; the pos-
terior  surface with the semitendinosus, semimembranosus, bi-
ceps, gluteus  maximus,  and the  sciatic  nerve.   The inner
border is much  thicker above than below, and is connected
with the  fascia lata and gracilis.
  The office of the adductors is — 1st, to move the thigh and
leg inwards ; 2d, to roll it outwards  ; 3d, to  bend the thigh on
the pelvis ; and lastly, to keep the pelvis  firm in the erect po-
sition of the trunk.   The  action of the fibres varies according
to the obliquity of their attachments. 
294
MUSCULAR  SYSTEM
POSTERIOR FEMORAL REGION.
BICEPS  FEMORIS.
  The biceps femoris  is sit-
uated at the back part of the
thigh,  and forms  the outer
hamstring.  It is divided in-
to two portions, one long and
the other short.   The long
portion is attached superior-
ly at a, by a tendon, to the
outer  part of the tuberosity
of the ischium, and descend-
ing,  forms  a thick,  fleshy
mass ;  its short portion, 6,  is
fixed by tendinous and fleshy
fibres  to the linea  aspera im-
mediately below the gluteus
maximus, and to the oblique
ridge  passing from the con-
dyle,  where  it is  connected
with the fibres of the vastus
externus.   The  two  heads
are united at an acute angle
a little above  the  external
condyle  of the  femur, and
terminate in a strong tendon,
c, which  is  attached at d,
to the outside of the head of
the fibula.
  The posterior  surface of
this muscle is connected with
 
OF  THE  INFERIOR EXTREMITY.        295
the gluteus maximus and the fascia lata; the anterior surface
with the semitendinosus, triceps, and adductor magnus muscles,
the sciatic nerve, the femur, and the external  lateral ligament
of the knee.  The long portion is placed over the short por-
tion which is connected with the  external superior articular
artery and the external head of the gastrocnemius.   The inner
border unites with the preceding muscle to form the ham.
   The biceps is a powerful flexor of the  leg  upon  the thigh,
or the  latter upon the leg; its long portion is  capable of ex-
tending the thigh upon the pelvis,  or  of keeping  the pelvis
erect.   It also assists in turning the leg outwards.
                     SEMITENDINOSUS.

  This muscle, e, is placed between the biceps femoris  and
gracilis :  we may also see it in  Fig. 166, c, k;  it is attached
superiorly, in common with the biceps, by aponeurotic fibres to
the tuberosity of the ischium ;  it has also some fleshy fibres
fixed to that  projection  more outwardly, and is connected for
several inches, at/ with  the commencement of the  biceps.
The fleshy mass runs down the back of the thigh, forms a long
round tendon, g,  which  passing round  the  inner side of  the
knee, becomes flattened, and is reflected forward to be inserted
into the inner side of the ridge of the tibia, a little below  the
tubercle, and is connected with the under edge of the tendon
of the gracilis, marked in this figure, h.
  The posterior  surface  of  the semitendinosus is connected
with the  fascia lata, and a little  at its upper part with the glu-
teus maximus ; the anterior surface with the semimembrano-
sus and adductor  magnus.
  The  office of  this  muscle  is to bend the  leg  backwards 
 296                MUSCULAR  SYSTEM

 and  a little  inwards, and  to  assist  in  keeping the  pelvis
 erect.

                     SEMIMEMBRANOSUS.

   This muscle, i, is situated behind the preceding muscle, and
 with it  properly  forms the inner hamstring.   The tendons of
 the  sartorius and gracilis are  sometimes enumerated  as part of
 the  inner hamstring, but they lie more  anteriorly.   The upper
 portion is best displayed in Fig. 166, and is superiorly attached,
 at d, to the outer part of  the tuberosity of  the  ischium.  It
 forms a fleshy mass in the middle  and  back part  of the thigh;
 and inferiorly terminates obliquely  in a  flat tendon, Fig. 168, i,
.which passing behind the inner condyle is spread  out  at k, in
 an aponeurotic expansion, which  covers  and strengthens the
 capsule of the knee joint, and is attached, at I, to the inner and
 back part of the head of the tibia.
   The offices of this muscle  are the same as those of the pre-
 ceding muscle.
   The posterior surface of the semimembranosus is connected
 with the biceps, semitendinosus,  and fascia lata; the anterior
 surface with the quadratus  femoris, adductor  magnus, and in-
 ternal head of the gastrocnemius, popliteal artery,  and the knee
joint.   Its outer  border  is connected with the sciatic nerve,
 and  concurs with the biceps to form the cavity of the ham ;
 the inner border is covered by the gracilis and the  cavity of the
 fascia lata.
                 TENSOR VAGINA  FEMORIS.

  This muscle, Fig. 164, a, is  situated at the upper and outer
part of the  thigh ; it  is  attached externally to the anterior
and  superior iliac  spine, between the  sartorius and gluteus 
OF THE  INFERIOR EXTREMITY.        297
medius, by a very short tendon ;  the fleshy fibres descend nearly
vertically,  diverging  as  they proceed, and about three inches
above the great trochanter terminate in the laminae of the femo-
ral aponeurosis.
  The outer surface  is connected to a thin lamina of the apon-
eurosis of the  thigh ;  the inner to another aponeurotic plate,
which separates the rectus femoris from  the  triceps extensor
cruris.   It also covers a portion  of the gluteus medius and glu-
teus minimus muscles.  The principal action of this muscle is
to stretch the aponeurosis which envelopes the  muscles of the
thigh.   It also carries the limb outwards, separating it from the
other.
               APONEUROSIS OF THE  THIGH.

   The inferior extremities, like  the superior, are enveloped  by
a strong  tendinous web.   In the thigh  it is  frequently termed
the fascia lata femoris ;  and is composed of strong tendinous
and ligamentous fibres, which cover all the muscles, and indeed
send septa or partitions  between them.   On  the outer part,  it
is very strong and tendinous ; but  in front,  and  on the inner
part, it is thin, and  composed of a mere condensed cellular
membrane.
   Superiorly and anteriorly the aponeurosis of the thigh is con-
tinuous with the fibres of the crural arch, and  is fixed posteriorly
to the sacrum and os coccygis ;  on the outer side,  it \-z inserted
into the crest of the  ilium  ; on the inner side, it is continuous
with the  ligaments of the pubis.   Inferiorly, this aponeurosis  is
blended round the knee with that of the leg.
  There is a  considerable opening  beneath  the  crural arch,
through  which the crural vein passes.   This  opening is formed
in  the following manner: —The aponeurosis being composed of
two portions, the  iliac and pubic, the former is folded in  the
   vol.  i.              39 
298
MUSCULAR SYSTEM
shape of a sickle at  that part where it ceases to be united to
the crural arch.   The concavity of this fold looks downwards
and inwards, and is termed the  falciform process ;  the latter,
or pubic portion, coming from the pubes,  passes  over  the pec-
tineus and adductors, and unites with the iliac portion beneath
the point where the saphena vein joins  the femoral. 
OF THE INFERIOR  EXTREMITY.         299
MUSCLES  OF  THE  LEG.
ANTERIOR REGION OF THE LEG.
TIBIALIS ANTICUS.
a-
   This muscle, Fig. 169, a, b, is              Fig. 169.
situated quite superficially on  the
fibular side of the tibia.  It is at-
tached superiorly to the external
tuberosity  and outer  surface  of
that bone, and to nearly half of the
interosseous  ligament,  g;  from
these surfaces it continues  to  ad-
here down two-thirds of the length
of the leg.   Its  fibres also  are at-
tached to the inner surface  of  the
aponeurosis of  the leg, and to the
intermuscular septa.   The fleshy
mass  descends  obliquely,  and
forming a  strong  tendon, crosses
from the outside to  the fore part
of the tibia, and passing through
a distinct ring of (b) the annular
ligament,  near  the  inner  ankle,
and  running over the  astragalus
and os naviculare, it is  inferiorly
inserted, at c,  into  the os  cunei-
forme internum, and the posterior
extremity of the metatarsal bone
of the great toe.
  The  anterior  surface of this
muscle, at its superior part,  firmly
adheres to the aponeurosis of the tibia;  it  is also connected
mm 
300
MUSCULAR  SYSTEM
with the annular ligament of the tarsus, and the  dorsal apon-
eurosis of the foot ;  on  the inner side with the tibia ;  on the
outer with  the extensor communis  digitorum pedis, extensor
proprius  pollicis  pedis, the anterior tibial  vessels and nerves.
The posterior border is placed upon the interosseous ligament,
the tibia, the articulation of the ankle, and the upper and inner
part of the tarsus.
  The office of the tibialis anticus is to bend the  foot upwards
and inwards.   It is also a flexor of the leg on the foot, and it
prevents  the limb from falling backwards in the standing  pos-
ture.
                     PERONEUS TERT1US.

   The fleshy  fibres  of this muscle, d, e, and Fig. 171, e,/
 are  almost inseparably connected with  the  long extensor of
 the toes, and indeed it may be said to be the outer portion of
 it.   It is attached superiorly to the inferior third of the anterior
 border of the fibula, and to the  neighboring part of the internal
 surface.   It sends  its fleshy  fibres forwards to a tendon which
 passes under the annular  ligament of the tarsus  in  the same
 groove as those of d,  Fig.  171,  and is attached inferiorly, at e,
 to the posterior part of the metatarsal bone of the little toe.
   The outer surface  of the  peroneus tertius is connected with
 the aponeurosis of the leg ; the inner surface with the exten-
sor brevis  communis  digitorum pedis.  In  the foot  it passes
over the extensor digitorum pedis and the first metatarsal bone :
its posterior border is  placed  upon the fibula  and interosseous
 ligament.
  The office of this muscle is to bend the foot upon the leg,
raising its outer edge ; it also bends the leg on the foot. 
OF THE  INFERIOR EXTREMITY.         301
EXTENSOR LONGUS  DIGITORUM PEDIS.
  This muscle, a, is placed en-                 Fig. 170.
tirely superficially between a,
the tibialis  anticus, Fig.  169,
and d, e, the  peroneus tertius,
being firmly connected to them
by  the  intermuscular  mem-
branes.   In  the figure before
us it is represented drawn aside
by  a hook  at  a ; superiorly it
is attached by aponeurotic and
fleshy fibres,  at b,  to the  ex-
ternal tuberosity of  the tibia;
to the head, and to almost the
whole anterior part of  the in-
ternal surface  of the  fibula, to
the interosseous  ligament, and
to the aponeurosis of the leg,
and  the intermuscular septa.
The  fleshy fibres  proceeding
from these  different directions,
pass obliquely into  a  tendon
marked  d,  Fig.  171,  which
below the middle of  the leg is
divided  into  four  continuous
portions, and pass under c, Fig.
170,  the  annular   ligament,
then over  the upper part  of
the foot, and are distributed to  the posterior extremity of the
first phalanx of the four small toes,  by flat tendons, which
afterwards expand upon the upper surface of the toes.
 
302
MUSCULAR  SYSTEM
   The anterior border of this long extensor of the toes is con-
nected with the aponeurosis of the tibia, the annular ligament
of the tarsus, and the integuments ; the posterior border with
the fibula, the interosseous  ligament, the tibia, the ankle joint,
and  the  extensor brevis digitorum and  the  toes.  The inner
-corresponds to the tibialis anticus and  extensor proprius pollicis
pedis.  The outer is intimately united above with the peroneus
longus. at the middle with the peroneus brevis, and below with
the peroneus tertius : see Fig. 171.
   The office of this muscle is to extend  all  the joints  of the
small toes, and to assist in raising the  foot.
           EXTENSOR PROPRIUS POLLICIS PEDIS.

   The fleshy fibres of this muscle, d, are situated between the
long extensor of the  toes and  the anterior tibial muscle, and
cannot be exhibited until those muscles are separated from each
other ;  but the tendon is superficial, passing between the ten-
dons  of those two muscles.   It is attached superiorly to the
anterior part  of the middle third  of the inner surface  of the
fibula, and to the adjacent part of the  interosseous ligament;
the muscular fibres terminate in a tendon  which passes  in a
particular groove  under c,  the annular ligament; runs along
the inner edge of the foot, and is inserted, at e, into the upper
surface of the  posterior extremity of the last phalanx  of  the
great toe.
   The inner surface  of this muscle is connected with the tibi-
alis anticus, and anterior  tibial vessels and nerves ;  the outer
surface with the extensor communis digitorum ;  the  anterior
border is concealed above between the  tibialis anticus and ex-
tensor digitorum, and  is covered by the aponeurosis of the tibia
and the  integuments.   The posterior border is placed  on the 
OF  THE  INFERIOR EXTREMITY.         303
fibula,  the interosseous ligament, the tibia, the  anterior tibial
artery, the articulation of the tibia and tarsus, and  upon the
back of the foot and great toe.
  The office of this muscle is to extend the great toe ; it  also
bends the leg on the foot and the foot on the leg. 
304
MUSCULAR  SYSTEM
PERONEAL REGION.
PERONEUS  LONGUS.
          ^S-171,                This muscle,  g,  and Fig.
                               174, d, is situated at the exter-
                               nal  part of the leg.  Its fleshy
                               fibres are  quite superficial.  It
                               is attached superiorly  to the
                               outer side  of the upper extrem-
                               ity  of the fibula,  at g,  and to
                               one-third  of its length down-
                               wards, to the crural aponeurosis
                               and to  the aponeurotic septa
                               placed between the soleus and
                               flexor  longus pollicis  pedis on
                               one  side, and the extensor lon-
                               gus  pollicis pedis on the other
                               side; the  fibres run obliquely
                               outwards into  a tendon, which
                               passes behind  the outer ankle
                               through  a  groove which  is com-
                               mon to it with  the peroneus ter-
                               tius  : thus, at the lower end  of
                               the  fibula, these tendons  are
                               bound down  by  a  tendinous
                               bridle.   The tendon of the pe-
                               roneus longus is then conducted
                               through  a channel in the os cal-
cis and os cuboides, extends obliquely  across  the sole of the
foot, and is attached to the posterior extremity of the metatar-
sal bone of the great toe, and to the  os cuneiforme internum.*
* This insertion is distinctly seen in Fig. 174. 
OF  THE  INFERIOR EXTREMITY.        305
  The outer suface of the peroneus longus  is connected with
the aponeurosis of the tibia ; the inner surface with  the fibula,
extensor digitorum communis, and peroneus brevis ;  the poste-
rior surface corresponds to the soleus above and below, to the
flexor longus pollicis.  The several connexions of the tendon
have already been noticed.
  The office of this  muscle is to turn the foot outward, and to
assist in extending it.
                    PERONEUS BREVIS.

  This muscle is situated between the extensor longus  digito-
rum and peroneus longus ;  its muscular fibres are concealed by
those of the latter muscle.   It is attached superiorly to  the in-
ferior half of the outer surface of the fibula, and to the  inter-
muscular  aponeurosis and to the aponeurosis of the  leg.   The
fibres run obliquely towards a tendon which  passes in a  groove
of the fibula at the outer ankle, where it is inclosed in tie same
tendinous ring with the peroneus longus.  It is continued through
a channel on the outside of the os calcis, and is attached to the
superior part of the posterior extremity of the  metatarsal bone
of the little  toe : see Fig.  174, g.
  The outer surface of the peroneus brevis is connected with
the aponeurosis of the tibia and  peroneus longus :  the inner
surface with the fibula, the extensor digitorum communis, and
the peroneus tertius  above, and with the flexor longus pollicis
below.
  The office of this muscle is to turn  the foot outwards, and
somewhat to extend it.
  vol. i.                     40 
306
MUSCULAR SYSTEM
                POSTERIOR REGION OF THE LEG.

         GASTROCNEMIUS EXTERNUS ET INTERNUS.

  These muscles are  extremely large            F'S-172-
and strong, and principally  form the
calf of the leg.   They are  separated
above into two flat fleshy masses, but
are united below, where they present
the strongest  tendon  of the  whole
body.  The internal muscle is attach-
ed superiorly, at a, to the back part  of
the inner condyle  of the femur ; the
external muscle is attached in the same
manner, at 6, to the external condyle.
Each of  these muscles  forms a  large
fleshy mass,  which is united  below the
ham in a central fibrous line near the
middle of the  leg : at c, they become
a broad aponeurosis, which  as  it ap-
proaches the heel, forms with the two
tendons of the subsequent muscles a
strong  round chord, at d, termed the
tendo-Achillis, which is fixed at  t,
the posterior extremity of the os cal-
cis.
  The  anterior surface of the gas-
trocnemii  is  connected with the con-
dyles of the  femur, and the synovial  membrane of the articula-
tion of the knee ; the outer muscle with the popliteus ;  the in-
ner with the semimembranosus,  the  popliteal  artery,  the plan-
taris and soleus muscles ; in the  remainder of its  extent it is in
 
OF  THE  INFERIOR EXTREMITY.        307
apposition with the soleus.  The posterior surface is connected
with the  integuments.
  The separation of the two muscles, at  6, a, contributes to
form the  ham.
  The office of these muscles is to extend the foot.  They are
seen very strongly  acting in dancing, running, leaping,  and
when we are raising ourselves on the toes.   From their  origin
on the femur, they also have the  power of bending the leg  on
the thigh. 
308
MUSCULAR  SYSTEM
SOLEUS.
If
     Fig. 173.               This muscle is placed under the pre-
                         ceding, but part of it appears on each
                         side of those muscles.   Superiorly it is
                         attached, by the  external portion at a,
                         to the posterior part of the head of the
                         fibula, and to the superior third of the
                         oblique line on the posterior surface of
                         the tibia, and to a portion of the inter-
                         nal border of that bone below /  the
                         popliteus, the fleshy fibres terminating,
                         at 6, in a  broad  aponeurosis ; inferi-
                         orly,  this  aponeurosis  is  inseparably
                         united with that of c, the gastrocnemii,
                         forming the  tendo-Achillis, which is
                         inserted, at g,  into the os calcis.*
                           The posterior  surface  of the soleus
                         is connected  with  the  gastrocnemii
                         and  plantaris, and with the aponeuro-
                         sis of the  leg; the anterior  surface
                         with  the peroneus longus,  popliteus,
                         flexor longus digitorum, flexor longus
                         pollicis, and  tibialis posticus muscles,
                         a portion  of the back  of the  fibula,
                         the popliteal, posterior tibial, and fibu-
                         lar vessels.
   This muscle assists the gastrocnemii  in  extending the foot
and in raising the heel in progression.
  * From the circumstance of the three  muscles being united into one ten-
don, H. Cloquet has described them as a single muscle, under the name of
rtriceps extensor pedis. 
OF  THE  INFERIOR EXTREMITY.        309
                        PLANTARIS.

  This muscle, which is long, and extremely thin and narrow,
is situated under the outer portion of the gastrocnemius.  It is
attached superiorly, at d, to the posterior part  of the external
condyle of the  femur, and adheres  to the capsule of the knee
joint, and to  the  tendon  of the gastrocnemius externus.   It
forms behind  the joint   a small fleshy fasciculus, which passes
over the popliteus, / and sends a very long and slender tendon,
e, obliquely  inwards, which accompanies c, the tendo-Achillis,
to be attached with it, at g, to the os calcis.
  The posterior surface of the plantaris is connected with the
gastrocnemii and integuments;  the  anterior surface with the
ligaments at the posterior part of the knee joint, the popliteal
vessels, and the popliteus and soleus muscles.
  The particular use  of this muscle has been a question with
physiologists ;  although   it  is generally classed  with  the exten-
sors of the foot, it is so extremely slender that it can have but
little power in the motions  of the limb.   I am of opinion, that
its office is solely to contract the foldings of  the capsule, so as
to prevent injury in the  flexion of the knee joint.
                        POPLITEUS.

  This is a small muscle, Fig. 174, a, Fig. 173,/ of a trian-
gular figure, situated across the back  part of the knee joint.  It
is attached superiorly within the capsule of the knee joint, by a
round tendon, to  the depression of the external condyle of the
femur; it adheres  to the  posterior  and  outer surface of the
semilunar cartilage ; and at the back part of the condyle  it
perforates the capsular  ligament, and forms a  fleshy mass, 
310
MUSCULAR  SYSTEM
which, passing obliquely inwards, is attached inferiorly, broad,
thin, and fleshy, to the superior  triangular surface at the back
part of the tibia.
   The posterior surface of the  popliteus is connected with the
gastrocnemii  and plantaris muscles, the popliteal vessels, and
the posterior  tibial nerve ; the anterior  surface with  the arti-
culation of the tibia and fibula, the tibialis posticus muscle, and
the tibia.   The outer margin is united  above by a  thin  mem-
brane with the upper part of the fibula and soleus.
   The office of this muscle  is to bend the thigh and the leg ;
but chiefly, like the  preceding, it  prevents the capsule from
being compressed in the motions  of the knee joint. 
OF THE  INFERIOR  EXTREMITY.
311
FLEXOR LONGUS DIGITORUM PEDIS.
  This muscle 6, is  situated be-
neath  the  soleus; it  is  attached
superiorly to  the  posterior surface
of the tibia,  and  to  the superior
oblique line,  until it arrives within
three inches  of the  ankle.   The
fleshy fibres  pass  obliquely into a
tendon at the posterior edge of the
muscle ;  this tendon  runs behind
the inner ankle in a groove of the
tibia,  and  is secured in  this situa-
tion by a strong  ligament, which
is extended from the ankle to the
os calcis, and having  received a
tendinous slip from the flexor lon-
gus pollicis, divides about the mid-
dle  of the sole  of  the   foot into
four tendons, which  pass through
slips in the tendons  of the flexor
digitorum  brevis, and are finally
attached  to  the  posterior part  of
the  inferior  surface  of  the  last
phalanx of the four small toes.
   The posterior surface  of this
muscle is  connected with  the  so-
leus  muscle, the  tibial  aponeurosis,  and the  posterior tibial
artery; the  anterior surface  with  the tibia and  the tibialis
posticus  muscle.   The outer border is united with that muscle,
and with the flexor  proprius pollicis pedis.   In the  foot, the
upper surface is  connected with the deep-seated  muscles  of
the sole, and the lower surface of its  tendons  with the adductor
 
312
MUSCULAR  SYSTEM
pollicis, flexor brevis digitorum, adductor minimi digiti muscles,
and the plantar nerve.
   The office of this muscle is to bend the last joint  of the
toes, to extend the foot; and  it is of great use in walking and
standing.


             FLEXOR LONGUS POLLICIS PEDIS.

   This muscle, c, e, Fig. 174, is placed  on the  outer  side of
the preceding,  between  that muscle and the peroneus longus.
It is attached superiorly by fleshy fibres to  the middle part of
the back  of the fibula, to the  interosseous ligament, and the
aponeurotic septa; the muscular fibres, c, terminate in a tendon
at e, which passes behind the inner ankle ;  (it is found further
back, that is, nearer the os calcis, than  the flexor longus digi-
torum pedis) ; and in the sole of the foot it crosses  the tendon
of that  muscle to be ultimately  attached at/  the last joint  of
the groat  toe.
   The  posterior surface of this muscle is connected with the
soleus and aponeurosis of the  tibia ; the anterior surface with
the fibula, the tibialis posticus, and the  flexor longus communis
muscles, the tibia, and the interosseous  ligament.   Its tendon
is enveloped by synovial membranes behind the  ankle  joint,
and under the great toe, and by  the flexor  brevis pollicis un-
der the sole of the foot.
   This muscle bends the great toe, and assists in extending the
foot on the leg. 
OF THE  INFERIOR  EXTREMITY.        313
TIBIALIS POSTICUS.
    The flexor longus  digitorum pe-
 dis, and  the flexor longus  pollicis
 pedis, are here removed to show the
 situation of the tibialis posticus ;  the
 muscles which  cover the  tendon in
 the sole of the foot also are  separa-
 ted to exhibit  its inferior  attach-
 ment.  Superiorly, the tibialis pos-
 ticus is attached  to  the posterior
 surface of the tibia at c, to the fibula
 at/ to the surface of the  interosse-
 ous ligament, and to  the aponeu-
 rotic septa; the fibres pass obliquely,
 at  b,  towards  a  central tendon,
 which passes behind  the inner an-
 kle in a channel  of the tibia, and is
 inferiorly  inserted into the internal
 and inferior part of the os navicu-
 lare, sending tendinous filaments to
 the adjacent  bones.
   The anterior surface of the tibi-
 alis posticus is connected  with  the
 tibia and  fibula, a  large extent of
 the interosseous  ligament, and the
 inferior part of  the os calcis  and scaphoides.   The posterior
surface is  covered by   the  soleus,  the flexor longus digitorum,
and the  flexor proprius pollicis  muscles,  and  by the fibrous
sheath of the inner malleolus.
  This muscle is an extensor of the foot, and draws it inwards.
  VOL.  I.                    41 
314
MUSCULAR  SYSTEM
M
USCLES  OF  THE FOOT.
DORSAL REGION.
EXTENSOR BREVIS  DIGITORUM  PEDIS.
Fig. 176.
                      This is a broad flat muscle, situated  on
                   the upper part of the foot; the tendons of
                   the long extensor pass  over  it, but in this
                   figure they are cut off near the toes.  Pos-
                   teriorly, the extensor brevis, a, is attached,
                   at c, to the upper surface of the os calcis,
                   the os  cuboides, and  the astragalus; its
                   fleshy fibres divide at b, b, b, b, into four
                   portions, each of which sends off a slender
                   tendon ; one of them is inserted anteriorly
                   into the first phalanx of the great toe,  the
                   others into all the small toes except  the
                   little one, and uniting with the tendons of
                   the extensor longus, they invest the upper
                   surface of the phalanges of the toes.
                      The upper surface of the short exten-
                   sor of the toes is connected  with a very
thin aponeurotic lamina extended  over the back of the foot, and
with the tendons of the long extensor of the toes ;  the inferior
surface with the tarsus, the metatarsus,  the  interossei  dorsales
muscles, and the phalanges.
   The office of this muscle is to assist in extending the first tour
toes, and it directs them a little outwards.
                   INTEROSSEI  EXTERNI.

  These small muscles are similar in form and arrangement to
those of the hand.  They are seen on the back of the foot at 
OF  THE  INFERIOR EXTREMITY.        315
b, b, b, b;  being attached  posteriorly between the metatarsal
bones of all the toes ; anteriorly, to the first joint of the smaller
toes.  They  are divided into  adductors  and  abductors  of the
toes.
  The office  of these muscles is to separate the toes.
PLANTAR REGION.
FLEXOR BREVIS DIGITORUM PEDIS.
   This  muscle, a, is  situated in  the        Fig. 177.
middle part of the sole of the foot.   Pos-
teriorly it is attached to the inferior sur-
face of d, the os calcis,  to the inner sur-
face of the plantar aponeurosis, and  to
the tendinous septa interposed  between
this muscle and the abductors of the toes.
It forms a thick fleshy mass, and divides
into  four tendons,  which,  having ad-
vanced beyond the tarsus, are split for
the passage of the long  flexor tendons,
and are ultimately attached to the infe-
rior surface of the second phalanx of the
four lesser toes.   The tendon to the lit-
tle toe, however, is not  always found.
   The  inferior surface of the short
flexor of  the toes is connected with the
plantar aponeurosis ; the superior surface with the lumbricales
and accessory muscle of the flexor longus, with  the  plantar
vessels and nerves, and with  the tendons of the long flexor.
The inner border is united to the adductor pollicis, posteriorly
but is separated from  it anteriorly by the tendon of the flexor
longus and a portion of the flexor brevis of the great toe ;  the
 
316
MUSCULAR  SYSTEM
outer border is contiguous anteriorly to the flexor  brevis mini-
mi digiti; posteriorly it is  annexed to  the  abductor minimi
digiti.
  This muscle bends the second joint of the toes.
                ABDUCTOR POLLICIS PEDIS.

   This muscle, c, is placed at the inner  edge of the foot.  It
is attached posteriorly to the lower and inner part of d, the os
calcis, and plantar aponeurosis ;  anteriorly  to the inner sesa-
moid bone, and base of the first bone of the great toe.
   The inferior surface of the adductor of the great toe is  con-
nected with the flexor communis digitorum pedis, the flexor ac-
cessorius, the lumbricales muscles, and the plantar aponeurosis ;
on the inner border with  the flexor brevis  pollicis  pedis, the
tendon of the peroneus longus, and  the outer side  of the meta-
tarsal bone; on the outer border with the interosseous muscles
and external plantar artery.
   The office of this muscle is to  carry the great toe  from the
others.
              ABDUCTOR  MINIMI DIGITI PEDIS.

  This muscle, o, is situated at the outer edge of  the  sole of
the foot.  Posteriorly, it is attached to the  outer side of d, the
os calcis, to a ligament which passes from that bone to the me-
tatarsal bone of the little toe, and to the plantar aponeurosis;
anteriorly, to the outside of the first bone of the little toe.
  This muscle carries the little toe outwards and downwards. 
OF THE INFERIOR EXTREMITY.         317
            FLEXOR DIGITORUM  ACCESSORIUS.*

  This  muscle, a, is situated at
the posterior  part of the sole of
the foot.  It is  attached on the
one part by aponeurotic fibres to
the inferior and internal surface of
c, the os  calcis,  from which it
proceeds in a horizontal direction;
on the other part  it  is inserted
into  the external border of b, the
tendon of the flexor longus digito-
rum  pedis.
   The  inferior surface is  con-
nected with the adductor pollicis
pedis, flexor brevis  digitorum pe-
dis,  adductor minimi digiti pedis,
and the plantar vessels and nerves;
the superior surface with  the os
calcis, the superficial inferior ligament of the os calcis and os
cuboides, and with  the abductor minimi digiti pedis.
   The  office of this muscle  is to assist the flexor longus digi-
torum pedis.

                     LUMBRICALES  PEDIS.

   These muscles, Fig. 178, c,  c, c, c, are similar in form and
 number to the lumbricales  of the hand ;  they are an apparatus
 of moving powers to assist the flexors  of the  toes.   The lum-
 bricales pedis are situated at the anterior part of the  foot, and
 extend from the tendons of the flexor longus digitorum pedis,
 to the first phalanx of the four lesser toes.
* Or massa carnea Jacobi  Sylvii. 
318
MUSCULAR  SYSTEM
  The inferior surfaces of the lumbricales are connected with
the plantar aponeurosis;  their superior surfaces with the ab-
ductor pollicis pedis, the transversus pedis, and with  the plan-
tar interosseous muscles.
  The office  of the lumbricales  is to bend  the toes, and to
draw  them a little inwards.
FLEXOR  BREVIS  POLLICIS PEDIS.
   The fleshy part of  this             Fig. 179.
muscle, a, is  connected al-
most inseparably to the ad-
ductor  and abductor  polli-
cis.   It is attached posteri-
orly to the fore part  of the
os calcis,  and  to  the  two
cuneiform bones ;  extending
anteriorly to the inferior and
lateral part of the first pha-
lanx of the great  toe,  and
to the sesamoid bones  of the
articulation.
   The inferior surface  of
the short flexor of the great
toe  is connected  with  the
plantar aponeurosis,  flexor
proprius,  and  adductor pollicis pedis ; the superior  surface
with  the  tendon  of  the  peroneus longus, and with  the first
metatarsal bone: the  inner edge  is  united  to the abductor
pollicis.
   The office of this  muscle  is to bend the first joint of the
great toe.
 
OF THE  INFERIOR EXTREMITY.        319
                ADDUCTOR  POLLICIS  PEDIS.

  This muscle, 6,  is placed at the internal part of the sole of
the foot.   Posteriorly, it is attached by aponeurotic and fleshy
fibres, at a, b, in two portions, to a strong ligament, which ex-
tends from the os calcis  to the os cuboides, and to the plantar
aponeurosis ;  from these different attachments it advances to be
inserted into  the outer sesamoid bone, and the base of  the first
phalanx of the great toe.
  The inferior surface  of this muscle is connected with the
plantar aponeurosis ;  the superior surface with the flexor ac-
cessorius, the flexor brevis pollicis, the  tendons of the  flexor
longus digitorum pedis, the tibialis anticus  and posticus, and
with the plantar vessels  and  nerves.
  This muscle carries the great toe outwards, and bends it a
little.

           FLEXOR BREVIS MINIMI  DIGITI PEDIS.

  This muscle, d, is situated at the outer edge of the sole  of the
foot.   It  is attached posteriorly to the metatarsal bone of the
little toe, and to the ligamentous  sheath of the tendon of the
peroneus longus; anteriorly, it is  inserted into the  first joint of
the little toe.
  The inferior surface is connected with the plantar  aponeu-
rosis and  abductor minimi digiti pedis; the  superior  surface
with the  fourth  metatarsal bone  and last plantar interosseous
muscle.
  The office of this  muscle is to assist in the flexion of the
little toe.

                    TRANSVERSUS PEDIS.

  This muscle, e, is situated at the anterior part of the sole of
the foot.  It is attached on the outer side to the  ligaments of 
320
MUSCULAR  SYSTEM
the four last articulations of the phalanges of the toes with the
metatarsus ; on the inner side, to the external border of the first
joint of the great toe.
   The  inferior surface of the transversus  pedis is connected
with the tendons of the long and short flexors of the  toes,  the
lumbricales, and the collateral vessels and nerves of the toes ;
the superior surface with the interosseous muscles.
   This muscle carries the great toe outwards, and brings  the
metatarsal bones nearer to each other.

                   INTEROSSEI INTERNI.

   These muscles, c, are three  in  number, and are situated  in
the sole of the foot.  They  are attached posteriorly between
the metatarsal bones of the four lesser toes ; anteriorly by ten-
dons to the inside of the first joints of the three smaller toes.
   The  office of these muscles is to  move  the three smaller
toes towards  the greater toe.

                APONEUROSIS OF THE  LEG.

   This is continuous superiorly with  the femoral aponeurosis;
it adheres strongly to every projecting point of bone,  as to the
head and spine of the tibia, and to   the fibula.   At  the inferior
part of the leg it has very  strong adhesions to the outer and
inner ankle:  it is continuous also with the annular ligament of
the instep, and is fixed  on the outer side to  the sheath of the
tendons of the peroneal muscles, and on  the  inner  side to the
internal annular ligament.

           ANNULAR  LIGAMENT OF THE INSTEP.

   This  is a transverse band of fibres which  binds down the
tendons of the extensors  of the  foot  and toes; the anterior 
             OF THE INFERIOR EXTREMITV.         321

part of the annular ligament is attached on the one side  to the
external part of the os calcis; on  the other side to the anterior
part of the inner malleolus.  It embraces  the tendons of the
extensor longus pollicis  pedis,  the extensor  longus digitorum
pedis, the peroneus tertius, and the tibialis anticus.   The inter-
nal annular ligament is  broader, extending from  the  internal
malleolus to the os calcis ; it forms with that bone a species of
canal, which contains the  sheaths of the tendons of the tibialis
posticus, the flexor longus digitorum  pedis, the flexor longus
pollicis pedis, and the plantar  vessels  and  nerves.   See  Fig.
170, and 171*

  * The plantar aponeurosis so much partakes of the nature of a ligament,
that I have thought proper to arrange and describe it with the ligaments.  See
p. 133.
VOL.  I.
42 
322
MUSCULAR SYSTEM.
        OBSERVATIONS ON THE MUSCLES.

   In describing the offices of muscles I have confined my ob-
 servations to their simple motions, but there are very few sim-
 ple motions in the animal economy :  almost every kind of con-
 traction is the effect of a combined effort of several of the mus-
 cles.   One action produces  another : for this reason,  the two
 points by which a muscle is  attached have an equal tendency
 to move ; if not prevented by the action of other  muscles, both
 extremes would come into motion when the muscle contracted :
 thus, by the contraction of the extensors of the  leg, the limb
 would be bent  on the foot equally with the foot on the leg,  if
 the foot was not fixed ; but  it can only be so fixed by means of
 muscles acting  in a  reverse, or opposition  to  the  extensors ;
 therefore, whenever two points of attachment are  movable, the
 simple motion of the one extreme supposes the contraction of a
 muscular power to fix the other.  No muscles are enabled to
 move singly without the aid of other muscles, except those
 which are inserted by one of their extremities into a fixed, and
 by the other into a movable  point, as those of the eye, and the
 greatest part of  the moving  powers of the face.   We may re-
 mark, however, that there is always an immovable line or point
 from which every ordinary motion originates, and one extremity
is always more movable than the other ; thus, although the two
attachments of  the  gastrocnemii  are movable,  yet these mus-
cles act more effectually upon the foot than upon  the femur.
  To ascertain the office of a muscle, we must examine its direc-
tion from the more fixed, up to the more movable point — the re-
verse of that direction is the line of action.  The tibialis anticus
directed downwards and inwards raises the foot and brings it out- 
OBSERVATIONS  ON  THE  MUSCLES.      323
wards ; the rectus femoris directed from the pelvis towards the
patella raises the leg without the least  deviation.   Every other
muscle, whatever may be its attachments, has the same disposi-
tion : they always act in the reverse of the line of their direction ;
the coraco-brachialis, which is directed downwards and outwards
from the shoulder towards  the  arm, moves  the  latter upwards
and inwards.   By this rule, when we see a muscle we may de-
cide for what uses it was intended.
   The whole effort of the contraction in long muscles is usually
concentrated on a single point of the tendon :  in  the greatest
part of wide muscles, on the contrary, the insertions being on
the sides, and by a  number  of  points, all the fibres have not a
uniform action.  The different parts of the  same muscle may
be intended  for very different, and  even  for opposite uses ;
thus, the  anterior fibres of the deltoides advance  the arm, the
posterior draw it backward, and the lower part of the serratus
major does not act like the upper; frequently, even  different
portions of the same muscle do not contract simultaneously : the
upper portion of the trapezius  may act  independently of the
lower ; the same may be observed of the muscles of deglutition.
In the long muscles, however, every fasciculus concurs to  pro-
duce the same  effect at the same moment.
   If a wide muscle is concentrated in one common point, as the
temporal  and deltoid,  which is attached to  a multiplicity of
points on the one part, and on  the other is attached by a single
tendon, then the average direction of all its fibres is to be taken
to ascertain its office.  If a muscle is attached by many  points
,at each extremity, the line of direction of its fasciculi must be
examined to judge of its  action.  It is in this way  we under-
stand the action of the rhomboideus, serratus magnus, etc.   In
those muscles which are reflected, as the  obliquus  superior of
the eye, the  circumflexus palati, the peronei, etc., the action of
the muscle must be calculated from the point of reflexion only.
The orbicular muscles, as  those situated around the lips, the 
324               MUSCULAR  SYSTEM.
eyes, etc., have in  general  no fixed point;  they are  intended
merely to contract  the aperture around which they are situated.
   Let it again be observed, that  with a  very  few exceptions,
the actions of muscles are associated.  A  number of muscles
are required, even to nod the head, to maintain the body erect,
to put  it in motion, or to  continue  it  in progression; and in
very great bodily efforts, all the voluntary muscles appear to be
in action.
   In early life, the muscular system appears to  be penetrated
with  less blood than at a later period, the muscles of the infant
being of a much paler color than those of the adult; as age ad-
vances they gradually  assume a  deeper  color, they receive a
greater supply  of  blood-vessels,  and consequently are more
abundantly nourished than many other  organs.   During the
period of infancy and youth, the conformation of  the male  and
female muscles  is analogous.   In the former,  after growth in
stature is completed, the muscles increase in bulk ; to  the slen-
der and rounded form of adolescence, alternate projections  and
depressions mark the outline of the more manly form ; and we
may remark at this  period the muscular system appears (if the
organs are well  exercised) through the integuments, the fleshy
masses of muscular  fibre forming prominences separated by dis-
tinct grooves.   Painters and sculptors pay great attention to
the developement of the muscles,  making them  characteristic
of the figures they represent under different circumstances and
modes of life ; as we may  observe in the statues of the Farnese
Hercules and Pancratiastse, contrasted with those of the Anti-
nous and Apollo Belvidere.
  As the muscles increase in thickness, they acquire more den-
sity.   A remarkable difference may be observed in the firmness
of the muscles, especially  in a state of contraction, in the adult
and in the  infant, and between  persons who are accustomed to
take a great deal of robust exercise and those who are less ac-
customed to exertion ;  thus, while the sedentary and  indolent 
OBSERVATIONS ON  THE MUSCLES.       325
are remarkable for the  flaccidity of their muscles, the active
have them firmly developed.   The gymnastic exercises are very
much calculated to produce this effect,  and to strengthen the
moving powers ; but such exercises should be taken gradually,
and youth should not be urged to exertions beyond those which
they can accomplish without subsequent painful sensations.
   In the prime of life, the color of the muscles is a deep  red;
in the subsequent stages of life they gradually fade ; but there
are other causes besides advanced  age which destroy  the  bril-
liancy of their hue, such as ill health, and excesses of any kind,
which have a depressing influence on the vital powers.
   As age advances,  the muscles  undergo other changes : the
fibres become tough and resistant, and their excess of density
seems to prevent  their contraction ; at least, they can no lon-
ger perform with such rapidity as formerly, nor can movements
be continued so long, for weariness sooner follows.   But though
in persons advanced in life the  fibres  are dense,  the general
feeling of the muscles is loose  and flaccid, and the calves of the
legs quiver in walking, as  if less capable of action.  Old age is
a period at which motion causes a tremor of the whole muscular
system.  Why is this ?  Bichat says, it is because  the mus-
cles no longer possess a sufficient degree of contractility, and
that  they are  thus too long   for the  spaces  which they  fill.
This appears to proceed from the contractility of the tissue being
reduced in  the last stage  of life.  We are convinced of this
fact by comparing a muscle divided transversely in a young and
in an aged person : in the  former it contracts much more  than
in the  latter.
   By the very great contractility of the muscles of youth, all
the fibres are drawn closer together during repose, as well as in
action ; but in the progress of age this effect is no  longer  pro-
duced :  these organs therefore remain lax and flaccid, a  phe-
nomenon which indicates the  low state of contractile power.
   As the blood flows in less quantity to  the  muscular system 
326
MUSCULAR  SYSTEM.
of infants, and increases  gradually as  persons  become of an
adult age, so the quantity of blood decreases as persons become
advanced in years ;  the vessels in old subjects become partially
obliterated, and the  parts being deprived of their former supply
of the vital fluid, are left in the state before described, possessed
of a  reduced state of vital contractility and sensibility.
   The condition of  the  muscular system after death depends
upon the causes which produced it;  in ordinary cases,  after a
short time the dead body  becomes stiff, and retains  the form  it
is placed in, until decomposition takes place ;  but in some par-
ticular cases, as in poisoning and suffocation from the fumes of
charcoal, and in several other instances, the  muscles never be-
come firm : all contractility is extinct,  and the body continues
soft and flexible. 
BURSAE.
327
             BURSJE MUCOSAE, or Mucous Bags.

  The structures we are  about to describe not only enter into
the composition of joints, but are placed between the tendons
and bones exposed to much friction, and therefore may be con-
sidered as auxiliaries to the moving powers.   The bursae muco-
sas are intended for the same purpose as the synovial membranes,
viz., to produce or secrete a fluid similar to the  synovia, which
lubricates contiguous surfaces.   Their structure  and anatomical
arrangement are nearly the same, both  being shut sacs.   Dr.
Monroe discovered and described 140 of them, and since which
several other bursae have  been described by Dr.  Rosenmuller
of Leipsic ; they perform the  office of friction-wheels in  ma-
chinery, and take off too severe pressure  or friction from the
bone or tendon.   Bursae vary considerably in size, as well as in
form, some being oval  or circular, others  elongated, so as to
form sheaths which  inclose tendons.   Thus,  where tendons are
retained in situ by fibrous sheaths, the contiguous surfaces are
invested by a bursal membrane reflected over them, as the dif-
ferent  flexor and extensor  tendons  in both  extremities ; and
also where a muscle has to slide over a bony  prominence, as
where the gluteus maximus passes over the great trochanter, a
bursa is interposed ; or where  processes of bone play on fibrous
structures, as between the acromion  and the  capsule of the
shoulder joint.  These instances will suffice to point out the
operation of the general principle which determines the forma-
tion of synovial or mucous bursae.   The following enumeration
is from Mr. Bell,  and constitute the principal  bursae of the hu-
man body.
   In connexion with the Shoulder Joint  :
   1st.  A very large  bursa under the acromion, and betwixt it
and the head  of the humerus. 
328
MUSCULAR SYSTEM.
   2d.   Between the head of the clavicle and the coracoid pro-
cess of the scapula.
   3d.   Upon the capsule of the shoulder joint and under the
tendon of the subscapularis muscle.
   4th.   Under the deltoid muscle.
   5th.   Under the tendon of the latissimus dorsi.

   The principal bursae around the Elbow Joint are,
   1st.  Between the tendon of the biceps flexor cubiti and the
radius.
   2d.   Over the round head of the radius  and the extensor
muscles.
   3d.   On  the olecranon and under the triceps tendon.

   About the Wrist,
   1st.  A  large bursa between the flexor  tendons and the
carpus
   2d.    On the trapezium.
   3d.    On the os pisiforme.
   4th.   On the back of the carpus and  under the extensor
carpi radialis.
   5th.   Between the ligament of the wrist and the  tendon of
the extensor carpi ulnaris.
   Besides these sacs or proper bursae, sheaths surround the ten-
dons of almost all the muscles of the wrist joint.

   On the Pelvis,
   1st.   A large bursa between the  gluteus  maximus and the
vastus externus.
   2d.   Between the capsule of the hip joint and the psoas
magnus and iliacus intemus.
   3d.   Under the pectinalis.
   4th.  A large one on the surface of  the  trochanter major,
under the gluteus minimus.
   5th.  On the os ischii  and under the origin of the biceps.
   6th.  Under the tendons of the rotators of the thigh bone. 
BURS2E.
329
   In the Thigh, and around the Knef. Joint,
   1st.  Under the tendon of the extensors of the leg, and com-
municating with the knee joint.
   2d.   Under the ligament of the patella.
   3d.   Between the insertion of the semimembranosus and the
origin of the gastrocnemius.
   4th.  Over the internal lateral ligament of the knee joint.
   5th.  Under the popliteus.
   Several irregular bursae are found around those tendons which
are inserted into the tibia and fibula.

   Around the Ankle  Joint.
   All the principal tendons  which cross the ankle joint have
bursae under or around them, as the tendon of the tibialis anti-
cus, the extensor proprius, the extensor digitorum, the peroneus
longus and brevis.   There is also a proper bursa between  the
tendo-Achillis and the os calcis ; another  under the flexor lon-
gus pollicis, and also under the flexor longus digitorum and the
tibialis posticus.
   It is necessary for the surgeon to know these bursae ; because,
after a sprain and injuries, effusion  takes  place  in them,  and
they present a puffy swelling over  the joint not easily under-
stood without the recollection of  the natural anatomical  struc-
ture.
VOL. I.
43 
ART.  V.
VASCULAR  SYSTEM.
CHAP. I.
ORGANS OF CIRCULATION.
THE  HEART AND ITS ENVELOPES
THE  PERICARDIUM.





     Fig. 180.
 
THE  PERICARDIUM.
331
  The heart is the central organ of circulation ; and the peri-
cardium, b,  bf is a membranous bag which encloses the  heart,
a, and the roots of the arterial and venous  trunks  which  issue
from it.   It is situated in the lower part of the anterior medias-
tinum, above the  aponeurotic  centre of the diaphragm.  It is
connected anteriorly with the pleura, the thymus gland, the ster-
num, and the cartilages of the sixth and seventh ribs of the left
side;  posteriorly with the bronchial tubes, the oesophagus, and
the descending aorta: laterally with the pleura, e, the phrenic
nerves, and the inner surface of the lungs.
  The pericardium is composed of two membranes, an outer
fibrous and an inner serous.
  The fibrous membrane is  intimately  united below  with the
aponeurosis of the diaphragm ;  it ascends around the heart, em-
braces it as far as the base, and is continued to a certain dis-
tance upon the trunks of the great vessels.   The  pericardium,
therefore, is not perforated by these vessels, but its fibrous lam-
ina forms sheaths for them.
  The serous membrane is much more extended than the fibrous
membrane ;  for after lining the inner surface of the pericardium,
it entirely covers the heart,  and is continued upon the  aorta
above its first curve ;  to the right,  it is  reflected  upon the su-
perior vena cava ; to the left, upon the pulmonary artery before
its bifurcation, and upon the right pulmonary veins immediately
after their issuing from  the  lungs.   This serous membrane of
the pericardium dips into all the irregularities of the surface of
the heart, where it is  extremely thin and transparent, and is not
easily demonstrated ;  it also adheres intimately to the fibrous
membrane, but it has very little attachment to the vessels, and
can be raised from their surface without difficulty.
   The inner surface of  this membrane is  smooth, glistening,
everywhere in contact with  itself, and is moistened with  a se-
rous fluid to prevent ill effect from the  heart's motion. 
332
THE  BLOOD.
  The arteries of the pericardium are very small, and are derived
from larger arteries in  the immediate vicinity.  The veins cor-
respond to the arteries, and  partly terminate in the vena azy-
gos.  There have not yet been any  nervous  filaments traced
into its laminae.
                        THE  BLOOD.

   I shall premise a few remarks on the blood, before I proceed
to describe the organs which circulate it.

   The general appearance of human blood  is too well known
to render it necessary for me to describe it.   The blood circu-
lates in the heart, arteries, and veins ; the estimated quantity is
about twenty-eight pounds in an adult.   In the veins it is of so
deep a color that it is generally termed black blood; in the ar-
teries it is of a bright vermilion color.
   In order to render the difference between venous and arterial
blood more distinct, Magendie has given the  following table
of them: —
	Venous Blood.	Arterial Blood.
Color,	Black red,	Vermilion red.
Odour,	- Weak,	Strong.
Temperature, -	101 • 75° F.	Near 104° F.
Capacity for caloric,	-852*	839.
Specific gravity,	1051t	1049.
Coagulation,	- Less rapid,	More rapid.
Serum,	More abundant,	Less abundant.
• Water being one thousand. — Dr. J. Davy.  Philosophical Trans. 1815.
t Water being one thousand. 
THE BLOOD.                   333
   The blood is the most important fluid of the body, and most
essential  to the  support of its functions.   Many  able  anato-
mists and physiologists have  considered it as a living fluid ;
and the  arguments of those who maintain its vitality are very
strong :  I consider,  stronger than those who take  an opposite
view of  the question.   While hot and in motion in its vessels,
the blood remains constantly fluid; when it cools  and is  at
rest, it coagulates  and becomes a gelatinous mass,  which grad-
ually separates into two parts: the one, the crassamentum  or
the more solid part, the other, the serum or fluid.
   The respective relations in  the  quantity of serum to the
crassamentum, and those of the coloring  matter to the fibrin,
are variable, according to  the  circumstances  of  age and the
state of the health.
   The crassamentum forms more than half of the blood ;  it is
plastic, thick, and in consistence  like a strong glutinous jelly,
which soon putrifies in  the air;  but  dried by a  gentle heat,
becomes  a dark brittle mass.   The surface of the coagulum,
after being exposed in a vessel  to atmospheric air, becomes of
a florid red color ; but the lower surface contiguous to the ves-
sel is of a deep black ;  the change of color on the surface is
supposed to be owing to the oxygen of the atmosphere uniting
with the  blood.  The crassamentum is composed of— 1st, red
globules; 2d, fibrin.   The  red  globules  are obtained  by
agitating  the crassamentum of  the blood in the serum ; when
the globules, on examination with a powerful  microscope, will
be found  floating in that fluid.   According to the observations
of Captain Kater  and Dr. Young, who  measured the red
globules of the blood with a micrometer, and thus agree  that
the size of them is  between ^Vrr ana"  <nrW °f an mcn in diam-
eter, or, taking the medium, svhs of an inch.*
* See also Sir E. Home's paper, Philosophical Transactions, 1819. 
334
THE  BLOOD.
   The red matter of  the blood  is soluble in water; when
dried and calcined, it yields a charcoal, which furnishes during
its combustion ammonial gas, and  gives the hundredth part of
its weight of ashes, composed of
  Oxide of iron,   .--..--.-    55.0
  Phosphate of lime, with phosphate of magnesia,     -    *    -   8.5
  Pure lime,......    .   .    .    .    17.5
  Carbonic acid,  --.---.-..  11.0
   The fibrin, separated from the  coloring  matter,  is  whitish,
insipid, and inodorous ;  elastic  when moist, but brittle  when
dry.   In distillation it gives out a great quantity of carbonate
of ammonia and carbon, the ashes of which contain phosphate
of lime, a little phosphate of magnesia, carbonate of lime, and
carbonate of soda.   A hundred parts of fibrin are composed of
  Carbon,..........53.360
  Oxygen,..........19.685
  Hydrogen,     .........    7.021
  Azote,...........19.934
   The serum is a transparent liquid, slightly yellow; its odour
and taste resemble the odour and taste  of the blood.  Accord-
ing to Mr. Brand, the serum is almost pure albumen, united
to soda, which holds it in a liquid  state.  At  a  temperature of
158° F. it becomes a  solid mass,  like  the white  of an egg,
and forms on coagulating numerous small  cells, which contain
a matter very analogous  to mucus. 
THE  BLOOD.
335
   According  to  Dr. Marcet,  one thousand  grains  of the
serum of human blood contain,*
  Water,    *    ■»........900.00
  Albumen,..........86.80
  Muco-extractive matter,   ..-..*.     4.00
  Muriate of Soda, with some muriate of Potash,   <■            6.60
  Subcarbonate of Soda,     -..-».-     1.65
  Sulphate of Potash,........0.35
  Phosphates of Lime, Iron, and Magnesia,  ....     0.60
                                                    1000.00
   From different analyses of blood, and as the processes of in-
vestigation are perfected, we discover in the blood all the prin-
ciples, all the elements of the various organs of the body.   We
are able  with confidence to point out its fibrin as the same
matter with the muscular fibre; the albumen, that which forms
cartilages, and so  great  a number of membranes and tissues ;
the adipose matter, when combined with osmazome and  albu-
men,  constitutes the nervous mass; the  phosphates of lime and
magnesia, which constitute a great portion of the bones ; the
elements of the most  remarkable excrementitious substances, as
urea and the yellow  matter of the  bile, the  urine,  and  that
which by  absorption extends  itself into the cellular  tissues
around contusions.^
   The  blood, therefore, is  the  common  source from which
every tissue of the body borrows  and chooses its materials ac-
cording to its  degree of sensibility, and appropriates them to
itself, and subsequently retains or rejects  them.   The  body
derives its nourishment from  the blood, which  supplies the
waste that is continually going on in the  animal frame; and
the reproduction of any  part which may have been  destroyed,
equally depends upon it.   The  blood, impelled by the heart,

  * Philosophical Transactions for 1819.  These results very nearly coincide
with an analysis of Berzelius.
  t See Magendie's Compendium of Physiology, Art. Blood. 
336
THE  HEART.
is transmitted by the  arteries to the most minute parts of the
body, building up  the several structures, and keeping them in
a state of repair.  The superabundant  quantity is returned to
the heart by the several veins ;  but as a large portion of it is
expended in preserving  the healthy state of the body, it is
necessary that a constant supply should  be provided, and this
is formed in abundance from both  animal and vegetable food.
THE HEART.

  Fig. 181.
  The heart is a hollow muscular organ :  its form is annexed.
It is  inclined forwards, downwards, and  outwards, and  from
right to left; its general connexions have been pointed out in de-
scribing the pericardium.  The position of the heart somewhat
changes as it follows the motions of the diaphragm in breathing, 
THE  HEART.
337
and its weight draws  it in  different directions according to the
inclination of the body.
  The anterior surface is  turned a little  upwards, and pre-
sents in its middle a groove passing from left to right obliquely
downwards, and in  which is lodged the anterior  coronary arte-
ry and vein in the midst of a  considerable  quantity of adipose
tissue.  The posterior surface is nearly horizontal, and rests
upon the aponeurotic centre of the diaphragm :  it  is traversed
almost  vertically by  a channel  which receives the  posterior
coronary artery and vein.   The base  of the heart is  situated
behind and to  the  right, and is separated from the vertebral
column by the aorta and the oesophagus.    There is  observed
on it an oblique  groove, which indicates the junction of the
auricles and ventricles.  The apex is inclined forwards and to
the left, and in the living body is felt beating in the interval of
the cartilages of the fifth and sixth ribs.
   The heart contains four cavities, which are termed  its auri-
cles and ventricles.   An auricle and  a ventricle is  placed to
the right, and  to the left the  same disposition is  observed.  On
each  side the auricle communicates  with the corresponding
ventricle.   In the right cavities there is  found black  blood,
which has been received from all parts of the body, and which
must be submitted incessantly to the action of the air in the
 lungs ; in the left cavities we find  red blood, which has been
 received  from the  lungs,  having already undergone  a certain
 change from  the atmosphere, for  the  purpose of  again circu-
 lating through the  whole body.
VOL. I.
44 
338
THE  HEART.
RIGHT   SIDE  OF  THE  HEART.
THE RIGHT  AURICLE.
   The rio-fit auricle is also called the anterior auricle ;  its situ-
ation is obvious in the figure before us.*  On the right side it
has a loose appendage with denticulated borders, which bear-
ing some resemblance to a dog's ear, the  whole cavity has ob-
tained the name of auricle.  The parietes  of this cavity, Fig.
181, n, are  so thin as to be  semitransparent; but in the inner
surface at c, Fig. 182, its muscular fasciculi are disposed some-
what like the teeth of a comb, therefore have been named mus-
culi pectinati.   Its posterior part b, presents the orifice of the
superior vena cava, inclining forwards and downwards ; this is
separated from a, d, the orifice of the inferior vena cava, by a
projection formed by a thickening of the  muscular coat, the tu-
berculum howeri.   The septum of the auricle is seen separa-

   * The venae cavae, the auricle, and its opening into the ventricle, are here
laid open. 
THE  HEART.
339
ting the right from the left;  it is thin, and  presents, at e, an
oval depression named fossa ovalis,  at  the  circumference of
which the fibres are thicker, forming  an elevated ring, called
the annulus ovalis.   The space occupied in the adult by  the
fossa ovalis, is in the foetus,  an aperture named  the foramen
ovale, which sometimes remains open  through life, the use of
which, before the period of birth, is to transmit the blood of the
inferior vena cava directly into the left auricle.   The orifice of
the inferior vena cava is furnished with  a  duplicature of the in-
ner membrane, which  advances into the  cavity of the auricle,
and is named the Eustachian valve, marked h, f;  its  dimen-
sions are more considerable in children, and  it becomes gradu-
ally obliterated with age.
   The auricle is a reservoir in which the blood is collected du-
ring the contraction of the ventricle.
                  THE RIGHT VENTRICLE.

  The ventricles are the most essential parts of the heart;  they
constitute the forcing machine of the blood, and therefore merit
the most particular notice.
  The right ventricle  has a triangular pyramidical form, the
base of which is turned upwards and backwards, being insensi-
bly lost  in  the corresponding auricle.   Anteriorly and  out-
wardly, the muscular parietes, marked 1, are thin and concave ;
the posterior and inner is  formed by a partition, which equally
belongs to the left ventricle.  The thickness of the parietes of
the right ventricle is unequal in the different  parts of their ex-
tent : the inner surface presenting a great number of muscular
fasciculi, as g, commonly  designated by the  name  of carnea
columna, which vary  very  much in size, length  and direction.
Their disposition is irregular, some taking a vertical course from 
340
THE  HEART.
 the apex to the base, while the others cross them in all sorts of
 directions, and form with them a confused network.
   Some of these fleshy columns are much larger than the others,
 and their number also varies from three or four to eight or nine.
 These are attached to some points of the parietes of the ventri-
 cle, and extending  from  the apex to  the base they terminate
 abruptly, each by several small white  tendinous strings, called
 corda tendina  which are fixed into  the  points of k, k, the tri-
 cuspid valve ;  in one part diverging from, at another part uni-
 ting with, each other.   There are other  muscular fasciculi at-
 tached to the parietes in the  manner of  pilasters ;  they  follow
 every variety of direction, and are interlaced with each  other,
 so as to represent network, leaving between them  depressions
 of different dimensions.
   The entrance from the right auricle  to the right ventricle is
 termed the auriculo-ventricular orifice, which is furnished with
 membranous folds,  k, k,  termed the tricuspid valve, on account
 of its being divided into  three triangular  portions, the form  of
 two of which we see in the figure.   One of the surfaces of the
 valve is turned towards the parietes  of the ventricle, the  other
 towards the cavity  of the auricle.   One of its borders is attach-
 ed to the circumference of the orifice, the other is divided into
three floating portions, which are held in situ by the cordae ten-
dinae, or tendons of the carnea?  columnae.  Tins valve is thin
and transparent in its whole extent, but becomes thicker  at its
free edge, for the attachment of the small tendons which I have
before described.
  There is another aperture of a smaller size  than the prece-
ding, and leads  to the pulmonary artery. 
THE  HEART.
341
COMMENCEMENT  OF THE  PULMONARY ARTERY.
Fig. 183.
  The office of this artery is to carry the blood into the lungs
to be submitted to the action of the air in respiration.   The
pulmonary artery arises from the left part of the right ventricle ;
its orifice is surrounded by a callous ring, which indicates  the
limits of the muscular fibres of the heart; this  orifice is more-
over furnished internally with three membranous folds, c, c, c,
which are named sigmoid or semilunar valves : their semicir-
cular form is seen  in this figure.   They  are adherent to the ar-
tery by their convex and inferior border, and present in the mid-
dle of the loose margin a small tubercle  of  a fibro-cartilaginous
texture, termed the corpus Arantii.*  These are thin and trans-
parent ; they are in contact at their  extremities, and when let
down they completely close the artery, and  thus prevent the
blood which it contains from again entering the ventricle.
  The pulmonary artery passes  obliquely upwards and  to the
* So named from Arantius, who first described them. 
342
THE  HEART
left side, crossing the  course of the aorta, beneath which it
passes, and to  which it is united by cellular and adipose tissue.
After a course  of  about two  inches, it divides near the second
dorsal vertebra into two branches, one for each lung.   Between
these branches we observe a  round ligament passing from  the
pulmonary artery  to the arch of the aorta :  this apparent liga-
ment is the remains of  a  tube which is named the ductus arte-
riosus, and which, in the foetus, as the lungs were  impervious,
transmitted the blood to the riirht ventricle.*


        THE  LEFT  SIDE  OF  THE  HEART.
THE LEFT  AURICLE.

       Fig. 184.
   This figure represents  a section of the left auricle and ven-
tricle.   The left auricle is situated at the posterior and left side
of the heart; its extent is narrower and longer than the  ri^ht.

  * The distribution of the pulmonary artery will be noticed in a subsequent
section. 
THE  HEART.
343
It presents at its superior and inner part, at a, an auricular ap-
pendage, similar to that of the right auricle, but smaller.  The
interior surface, or the cavity of this auricular appendix, con-
tains much fewer musculi pectinati than that of the right appen-
dage.  Below is the left auriculo-ventricular  orifice,  leading
to the left ventricle.  The right side is smooth, and formed by
the auricular septum.   We may observe  that the fossa ovalis
is here less distinct than on the right  side.   The left side is
perforated at b, d,  by  two corresponding pulmonary veins ; the
orifices are very near each other.   Like  the right pulmonary
at/, c, they are destitute of valves.
THE LEFT VENTRICLE.
Fig. 185.
  This ventricle is placed at the posterior part of the left side
of the  heart.  Observe at b, Fig. 185,  and at i, Fig. 184, the
great thickness of the muscular parietes.   The interior is fur- 
344
THE  HEART.
nished with a great number of fleshy  columns, termed carnea
columna, similar to those of the right ventricle, though less nu-
merous, and more irregularly disposed.   There are several larger
than others, as at g, directed from the apex of the heart to the
base, fixed by one of their extremities to the sides of the ven-
tricle, and terminating  in a multitude of very slender diverging
tendons, which  frequently cross each other, and are attached to
the loose edge of e, h,  the mitral valve.
  At the base of the left ventricle the opening into  the auricle
is marked by a whitish zone, to which is connected a fold of
membrane, e, h, called the mitral valve,  from its shape being
compared to a bishop's mitre.   It is divided into two portions,
to which  the tendons  of the carneae columna?  are attached.
There is another opening on  the right side, which leads  into the
aorta, Fig. 185, a, which is furnished at c, c,  c, with  three semi-
lunar valves, similar to those at  the entrance of the  pulmonary
artery.   Above the loose edge  of the semilunar  valves we ob-
serve the orifices of the two coronary arteries of the heart.
              ORGANIZATION OF  THE HEART.

  The tissue of the heart is formed of muscular fibres in  close
apposition with each other, taking somewhat of an irregular spi-
ral course from the base to the apex, and there, as it were, dip-
ping in and forming the carneae columna?.  The parietes of the
auricles are much thinner than those of the ventricles.  In the
right auricle the muscular tissue constitutes a stratum of lon-
gitudinal fibres towards  the  point of union of the two  vena?
cava?, where it is separated from the serous lamina of the peri-
cardium by a  considerable quantity of fat.   In the left auricle
the muscular stratum is much thicker and more uniform than in 
THE  HEART.
345
the right ;  the  muscular fibres extend from  the pulmonary
veins to the auricle, where they form a transverse  plane ; but
more deeply they cross  each other in a very irregular manner.
   The exact arrangement of the muscular fibres of the heart is
extremely difficult to determine;   they  intermingle with  each
other  without any apparent cellular tissue being  interposed;
Cowper,  and subsequently J. Cloquet,  represent them as
disposed in a spiral direction ;  but 1 have frequently examined
their fibres, which seem to commence at all points, and extend
in all directions;  indeed, Magendie confesses  that he found it
impossible to unravel them.
   The septum auriculorum forms a thicker and more uniform
layer; the muscular fibres of the right ventricle are interwoven
at acute angles  with  those of the left ;  with  a degree of
patience, however, they may be separated, so  as to divide the
heart into two portions, the one the right, the other the left.
   The membrane of the cavities of the heart is evidently con-
tinuous with  the membranes which line the vessels destined for
the circulation of the blood.   On the right side the inner coat
of the  venae cava? is extended to the  auricle, upon the mus-
cular fasciculi, and in  their  intervals  upon the  serous tissue
which covers the heart.  Beneath  the inferior vena cava it is
folded upon  itself, to  form the Eustachian valve.  Again, at
the circumference of  the auriculo-ventricular  orifice, it is sep-
arated from the muscular tissue by  a thin  layer of fat, which
constitutes the white circle we have before mentioned.  There
also it is folded, as it were,  on  itself, leaving the parietes of the
heart to form the tricuspid valve ; after which  we may trace it
through the  whole ventricle  and into  the pulmonary artery,
forming by its  folding  the  three  semilunar valves,  and con-
tinued to the most minute ramifications of that  vessel.
   The membrane of the left cavities  of the heart forms part
of the inner tunic of  the vessels that carry red blood ; it  ex-
   vol. i.                 45 
346
THE  HEART.
tends from the extremities of the pulmonary veins to the whole
cavity of the auricle, and  penetrates  into  the ventricle.  At
the entrance of  the latter  its  thickness increases, and  it is so
prolonged  and doubled on  itself as to form the mitral  valve;
we may then view this membrane, if we examine the aorta,
forming the semilunar valves, and extending itself into it, and
constituting a lining to all the vessels of the arterial system.
               THE VESSELS OF  THE HEART.

   There are two arteries  which  rise immediately from the
aorta, and are called coronary ;  these  terminate in veins which
have  the same name, discharging themselves into the right
auricle;  its lymphatics are very numerous, and pass before the
aorta and left bronchus.  The nerves  also which  come from
the cardiac  ganglion  are very thickly  distributed upon the
heart.   We must consider a portion of the  pericardium like-
wise as contributing to the structure of the heart, for its whole
exterior is invested with it. 
THE  HEART.
347
Fig. 186.
        GENERAL OBSERVATIONS ON THE HEART.*

  The office of  the  heart is  to force  the blood, though the
vassels which  are connected  with it, to the  remotest parts of
the body, and the same  force returns it to the heart by means
of the veins ;  thus the blood  is  incessantly flowing from the
heart, and again proceeding to it, through the whole period of
life, in one circuitous, continual, and interminable stream, hence
called the circulation.  Having studied the heart, we are now
prepared to understand its duplex structure and  functions, i. e.
there is an auricle and a ventricle on the right side, and similar
cavities on the left side :  the right  performs the less, or pul-
monic circulation ;  the left, the great, or systematic circula-
tion.   But to give a more detailed account of the process : 1st,

  * The weight of this organ is about ten ounces in an adult, or, as compared
to the body, as 1 to 200.
*•■£ 
348
THE  HEART.
the descending vena  cava, q, conveys the blood from the head
and upper extremities ; the ascending vena  cava,* o, collects
all the blood  from the lower part of the body ; they meet and
formlthe right auricle, n.  We may term this the first cavity of
the heart ;  its contraction carries the blood into the right ven-
tricle, b, which stimulated by  the quantity and quality of the
blood, contracts,  and  forces the  blood  through  the  lungs  by
means of the pulmonary artery, k, which divides into right and
left, to  convey the blood by the branches /, I,  which are dis-
tributed through all the cells of the lungs, to render it fit for the
general circulation.
  2d. The veins  of the  lungs, m, m, are  sometimes three, at
other  times four in number :  they return the blood, which has
been  purified  in  the  lungs, to  the left  auricle, r;  this cavity
contracts and fills the left ventricle, a, and  the muscular action
of this ventricle at each beat propels all the blood of the body,
communicating its vibrations to the extremest  vessels.   The
blood thus distributed by the large trunks, namely, the aorta,
c, e, f  the arteria innominata, g, the subclavian artery, h, and
the left carotid artery, i, to the  smaller branches, is brought
back by the veins which are continued from  their extremities;
this is a  fact proved by the veins being  filled when a fluid is
injected  into  the  arteries.   The  circulation  of the  blood also
may be seen in the pellucid parts of animals by the aid of a
microscope.

            * p, Veins from the liver, spleen, and bowels.
/ 
TABLE  OF   THE  ARTERIES.
                  1.   PULMONARY ARTERY.



                          II.   AORTA.



ARTERIES FURNISHED  BY THE AORTA AT ITS ORIGIN.



             I.  ANTERIOR AND POSTERIOR CORONARY.


     II.  ARTERIES FURNISHED BY THE ARCH OF THE  AORTA.
Primitive carotid.
Divided into external and internal carotids.
External carotid.
Temporal artery.
   Furnishes.
Superior thyroid.

Lingual, which
8. Internal maxillary artery. <
                        gives the dorsal and
                          two sublingual.
                        1. The inferior pala-
 3. External maxillary, | „   ,'   .  ,
   or facial, furnishes  1 J submental.
           '             3. coronary arteries
                       [_  of the lips.

 4. OccipM, which    {^sSlP0S,eri°r


 \hrchtMstr1"'{,hes,yl°oas,oid-
 6. Inferior pharyngeal.
 The external carotid terminates in  dividing
 into the temporal and internal maxillary.

         {Furnishes,
 1. The transverse artery of the face.
 2. The anterior auricular.
 3. The middle temporal.

f Furnishes thirteen branches,
   11. Middle meningeal.
   2. Inferior dental.
   3. Deep posterior temporal.
   14. Masseteric.
   5. Pterygoidean.
  6. Buccal.
   7. Anterior deep temporal.
   8. Alveolar.
   9. Infra-orbital.
 10. Vidian.
 11. Superior pharyngel.
 12. Superior palatine.
 13. Sphenopalatine. 
350             TABLE  OF  THE  ARTERIES.
Internal carotid.
Subclavian artery.
Axillary artery.
Brachial artery.
Furnishes,
 Ophthalmic
which gives
.
 The lachrymal.
 Central artery of the
retina.
 Supra-orbital.
 Posterior ciliary.
 Long ciliary.
 Superior  and  inferior
                    muscular.
                 7. Posterior and  anterior
                    ethmoidal.
                 8. .Superior  and  inferior
                    palpebral.
                 9. Nasal.
                 10. Frontal.
2. The communicating artery of Willis.
3. "Choroid artery.
4. Anterior cerebral.
5. Middle cerebral.
  Furnishes,
1. The verte-
  bral, which
  gives
fl. Theanteri-
|   or and poste-
   rior spinal.
 2. Inferior cer-
   ebellic.
    The basilar,-
   divided into
fl-
                                  The  su-
                                 perior ce-
                                 rebellic.
                                  The pos-
                                 terior ce-
                              (_  rebral.

2. Inferior thyroid, which gives the ascend-
  ing cervical.
I3'.
3.  Internal mammary,
  which gives
 The  anterior
mediastinal.
 Superior dia-
phragmatic.
  4.  Superior intercostal.
  5.  Transverse cervical.
  6.  Superior scapular.
  7.  Deep cervical. Continuing its course, the
    subclavian takes the name of axillary.

              Furnishes,
 fl.  Acromial.
 | 2.  Superior thoracic.
 j 3.  Inferior thoracic, or external mammary.
■{ 4.  Inferior scapular.
 j 5.  Posterior circumflex.
  6.  Anterior circumflex.
 (_ In continuing, it takes the name of brachial.

              Furnishes,
  {1.  Deep humeral or external collateral.
  2. Internal collateral.
  It divides afterwards into the radial and ulnar. 
TABLE  OF  THE  ARTERIES.             351
1.  Radial artery.
2.  Ulnar artery.
fl
         Furnishes,
.  The radial recurrent.
.  Dorsal artery of the carpus.
.  Dorsal artery of the metacarpus.
.  Dorsal artery of the thumb, and terminates
 in forming the deep palmar arch,

         Furnishes,
  The anterior and posterior ulnar recurrent.
  The  anterior and posterior interosseous,
 which furnishes the posterior radial recur-
 rent.  It terminates in forming the super-
 ficial palmar arch, which gives the collat-
 eral arteries of the fingers.
       ARTERIES FURNISHED BY THE AORTA IN THE THORAX.

1.  The right and left bronchial.

2.  Oesophageal, (four, five, or six in number.)

3.  Posterior mediastinal.

4.  Inferior intercostals, (eight, nine, or ten in number.)
      ARTERIES FURNISHED BY THE AORTA IN THE ABDOMEN.

1.  Inferior right and left diaphragmatic arteries.

                          f Divided into three
                             branches.
                           1. Coronary of the
                             stomach.
2.  Coeliac artery.
<
2.  The Hepatic,
  which gives
3.  The Splenic
  which gives
s    i   S1
9    [2.  '
Superior mesenteric  ar-
 tery.
Furnishes from its
  concavity,
    The pyloric.
    The gastro-epiploica
   dextra.
 3.  The cystic.
    The gastro-epiploica
   sinistra.
    The vasa brevia.

"1.  The superior, middle,
   and inferior right co-
   lic.
 2. From fifteen to twenty
   intestinal branches.
4.  Inferior mesenteric arte
    ry-
                                    Furnishes,
                          fl.  The superior,
                         -J  2.  The middle,
                          j  3.  The left colic; and divides into the supe-
                          rs  rior hemorrhoidal arteries.

5. The middle capsular arteries (two on either side.)

6. Renal or emulgent.

7. Spermatic.

8. Lumbar (four or five on either side ) 
352            TABLE  OF  THE  ARTERIES.
ARTERIES RESULTING  FROM  THE BIFURCATION  OF  THE
                               AORTA.
The aorta furnishes a little
  before its bifurcation,
Internal iliac artery.
External iliac artery.
Femoral artery.
Popliteal artery.
.  The middle sacral, and
 divides  into the  primi
 tive iliacs, which are
 vided into
md
ni- fl.
di-l 2.
The internal.
The external
iliac artery.
  Furnishes
The ilio-lumbar.
Lateral sacral.
Gluteal.
Umbilical.
Vesical.
Obturator.
Middle hemorrhoidal.
Uterine.        fl.  Inferiorha;morrhoi-
 9.  Vaginal.
10.  Ischiatic.
11.  Internal pudic,
  which gives
«»■
is
dal.
 Artery of the sep-
tum scroti.
  Transversus  peri-
naei.
 Artery of the cor-
pus cavernosum.
,  Dorsalis penis.
        Furnishes
 {1. The epigastric.
 2. Circumflexa ilii, and continues downward?
   under the name of the femoral artery.

f         Furnishes
I 1. External epigastric.
| 2. External  superficial and  deeply seated
   pudics.
'1.  The external and
   internal circumflex.
 2.  The superior mid-
   dle and inferior per-
   forating arteries.
•{ 3.  Profunda, which
    gives
  In  continuing  its*
    course it takes the
    name of popliteal.

 |r        Furnishes
  1.  The superior middle, external and inter'
    nal articular arteries.
  2.  The interior internal and external arteries
  3.  The anterior tibial; fl.  Tarsal.
     its  continuation  is I  2.  Metatarsal.
^    called the dorsal ar--(  3.  Interosseous.
     tery of  the  foot, J  4.  Dorsal  arteries
     which furnishes,    (^  of the great toe.
  The popliteal is divided
    into the peroneal and
    posterior tibial arte- 
TABLE  OF  THE  ARTERIES.             353
1.  Peroneal artery.
2.  Posterior tibial artery.
 Divided into the anterior and  posterior  fib-
   ular.

'Divided into internal  and external plantar.
   It forms, in anastomosing with  the con-
   tinuation of the anterior tibial, the plantar
   arch, from which the superior, posterior,
   inferior, and  anterior branches are  given
   off.                                *
VOL. I.
46 
354
THE  ARTERIES.
              OF THE ARTERIES  IN GENERAL.

   The arteries are those tubes by which the blood is distribut-
 ed to  every part of the body.   During  life they may be dis-
 tinguished  by their  pulsation,  and if wounded, by the florid
 color of the blood, and by its escaping per saltum, or by jets;
 after death they may  be distinguished  by  their thick whitish
 coats, which are elastic, for if cut  through they preserve a cir-
 cular  orifice ;  and lastly, by their having no  valves except  at
 their union with  the heart.
   We have  taken a review of the heart, which represents a
 root, the arteries forming, as it were, two highly ramified trees,
 of which the principal  trunk  is the aorta, commencing at the
 left ventricle of  the heart, branching out through  all  parts  of
 the system, and terminating in minute twigs  at the circumfer-
 ence of the body, limbs, and  internal organs.   The other arte-
 rial  trunk arises  from the right  ventricle, and  is  extended
 through the lungs.
   The arteries very frequently communicate with each other,
 so that the blood can pass from  one to the other;  sometimes
 such  communication takes  place between  trunks of an equal
 size,  as  in the  vertebral arteries, which  unite to  form the
 basilar ; more frequently a small twig joins  a more voluminous
 trunk, or a transverse branch unites two  separate trunks,  as in
 the anterior cerebral arteries ;  or,  lastly, two trunks by  their
 union  form an arch, as we observe in  the mesenteric  arteries.*
   As  the  arteries  are  further removed  from the heart,  their
 communications are more numerous.   In the ultimate branches
 their union is so exceedingly multiplied as to form an intricate
network, ramifying ad infinitum, and from which the veins and
exhalents  seem to originate.

  * The communication of arteries with each other is termed inosculation,
or anastomosis. 
THE  ARTERIES.
355
                 STRUCTURE OF  ARTERIES.

  The arteries  are  composed of three  membranes  or  coats,
embracing each  other I  the inner membrane  is similar and con-
tiguous with that which lines  the heart, being  very smooth,
thin, and transparent, and so fine as to have  no traces of fibres.
The outer membrane is dense  and compact, and seems  to be
continuous  with the surrounding  cellular tissue, and which is
formed of its compressed laminae; it is called the  cellular coat.
Between these two  coats  is a third membrane, which chiefly
forms the artery ;  it is of  a firm,  close texture, and strong in
proportion to the calibre of the vessel,  of a yellowish or gray
color, composed of distinct fibres  adherent  to each other, and
disposed  in concentric  layers,  intimately united to the external
or cellular coat, but being very  little  adherent  to the  inner
membrane.  This tissue  many anatomists  have denominated
the muscular coat; but it differs very materially from muscular
structure.  It  is  of  a  peculiar nature, very  dense, possessing
little extensibility, although it is elastic  and contractile.
  The arteries receive minute arteries (vasa vasorum,,)  which
enter into the  coats  of the artery, and form very complicated
meshes on the surface, and which pass into venules, terminating
in the trunks of the neighboring veins.*  No lymphatics have
been traced into them ; but their nerves are very apparent, and
are supplied chiefly  from the system of the ganglia.

  *The blood which flows through the artery is incapable of supplying
nourishment to it;  these small vessels support its vitality,  and are not sup-
plied by the artery  which they nourish, but by others in the vicinity. 
356
VASCULAR  SYSTEM
                        THE  AORTA.

   The aorta commences at the left ventricle;  it is connected
with the heart by a continuation of the lining membrane of that
cavity, prolonged  into its  interior,  and there forming  three
semilunar valves : see Fig. 185.
   At its origin,  the aorta is concealed by the pulmonary artery,
but which at a  short distance  leaves it, as  the  aorta  immedi-
ately is directed upwards and to the  right, and  crossing before
the vertebral column, forms a curve  called the arch of the
aorta, see Fig.  180, c: opposite the third  or  fourth  vertebra
it emerges from  the pericardium, and  occupies  the middle of
the vertebral column ;  it  is then directed a little backwards
and  to the left; from  this situation the aorta becomes  vertical,
and descends in  the  posterior mediastinum  upon the  anterior
and left part of the dorsal vertebrae ; it arrives at  the diaphragm,
see Fig. 130, n, and passes  along with  the  thoracic duct be-
tween its two pillars, f, e,  d, c, and terminates in the abdomen
by dividing at the fourth or fifth  lumbar vertebra.*  From  its
origin  to its curve it  is termed the ascending aorta, and from
the arch to its division  it is called the descending aorta, which
is again distinguished into the thoracic aorta and the abdominal
aorta.
   The aorta in  the pericardium, see Fig. 181, e, is embraced
by the pulmonary artery, k, on  the right,  and by the  vena
cava, q, on the left:  anteriorly, the mediastinum separates it
from the sternum.  Its arch lies at first on the  trachea, a  little
before the division of the latter, and  afterwards on the bodies
of the  second  and  third  dorsal  vertebrae.   In the  posterior
mediastinum  it  lies  on the  left of the  vertebral column, the
oesophagus, the thoracic duct, and the vena azygos.
* See Fig. 201. 
OF  THE  ARTERIES.
357
THE  ARTERIES  WHICH  THE  AORTA GIVES  OFF  AT  ITS
                          ORIGIN.

              THE RIGHT CORONARY ARTERY.

  This artery commences from  the  aorta  immediately above
the loose  edge of the semilunar valves ; and is seen in the
groove which separates the right auricle from  the correspond-
ing ventricle.   It  winds round the channel upon the posterior
surface of the heart, where it divides  in,to two branches, which
are distributed over the heart and extend to the apex.
   At its  commencement the  right  coronary  artery gives off
very small ramifications to the  aorta  and right auricle ; others
extend  over the venae cavae  and the interarticular septum ;
other branches descend upon the  right ventricle, and commu-
nicate with  the left coronary artery.


               THE  LEFT CORONARY ARTERY.

   The left  coronary  artery is smaller than  the right;  it  arises
like it from  the commencement  of the aorta, to the left of the
pulmonary artery.   It then  directs  itself downwards  between
the pulmonary artery and the left auricle, and enters the groove
of the anterior surface of the heart (see Fig. 181, s.) and runs
along its whole extent to the  apex.   It sends branches to the
aorta and the pulmonary artery, and to the auricle  and ventri-
cle ; and dividing into  very  numerous twigs  it communicates
with the  branches of the preceding artery.


       THE  ARTERIES  OF THE  ARCH OF THE  AORTA.

    There are  three arterial trunks arising from the arch of the
aorta, destined for the head and the  superior extremities; they 
358
VASCULAR  SYSTEM
are shown in Fig. 186, and designated the arteria innominata,
g; the left carotid, h; and the left subclavian artery, i.

                   ARTERIA  INNOMINATA.

   This artery ascends obliquely to the right, on the side of the
trachea, and after the course of an inch divides into two trunks,
of which the  one is the right carotid, the other the right sub-
clavian artery.


               PRIMITIVE  CAROTID ARTERIES.

                          Fig. 187.
 
OF  THE  ARTERIES.
359
   It has been already mentioned, that the right carotid artery
arises from the  arteria innominata, while the left takes its origin
from the aorta.  But their volume is precisely the same ; they
ascend obliquely on each side of the neck, a, to the  upper part
of the larynx, b, where  they divide into two branches, the ex-
ternal and the internal carotid artery.
   The interval between  these two arteries  is occupied by the
larynx, the trachea, and  the oesophagus.
   Anteriorly, the left carotid is connected with the left sub-
clavian vein, the thymus gland,  and the clavicle.  Posteriorly,
the common carotids are situated upon the vertebral  column,
and more immediately  upon  the inferior  thyroid arteries, the
longi colli, and  the recti capitis antici majores muscles.   Inter-
nally, they correspond  to the trachea, the thyroid  gland, the
larynx,  and  the  pharynx.   Externally,  they  are  connected
with the internal jugular vein, the pneumo-gastric nerves, and
the communicating cords of  the middle and superior cervical
ganglia.


               EXTERNAL CAROTID ARTERY.

   This artery extends from the upper part of the larynx to the
neck of the condyle of  the lower jaw, and is particularly des-
tined for the face and the exterior of the skull.  It  passes be-
hind the  posterior  portion of the digastric and the stylo-hyoid
muscles, where it crosses  its  direction, winding outwards and
backwards,  between  the zygomatic process  of the temporal
bone and  the angle of  the under  jaw; then divides into two
branches, which are named the temporal and internal maxillary
arteries.
   On the  outer side, inferiorly, the external  carotid is  con-
nected with the platysma myoides and integuments,  afterwards
with the  hypo-glossal nerve, the digastricus, and  the  stylo-
hyoid muscles ;  and lastly, it is covered by the parotid gland. 
360
VASCULAR SYSTEM
On the inner side, and  from below upwards,  it is  connected
with the internal carotid artery, the  stylo-pharyngeus, and the
stylo-glossus muscles, and  the styloid  process of the temporal
bone.
   The branches which this artery  furnishes  are— 1st, anteri-
orly,  the superior thyroid, the  external  maxillary,  and the
lingual; 2d,  posteriorly, the occipital and auricular; 3d, on
the inner side, the inferior pharyngeal, and  those by which  it
terminates ;  the temporal and the internal maxillary arteries.


ANTERIOR ERANCHES  OF THE EXTERNAL CAROTID ARTERY.

             I.   SUPERIOR THYROID ARTERY.

   This  artery is situated at the  fore  and upper part of the
neck ; it extends from the external carotid, a, to the larynx,  b,
and to  the  thyroid gland, p,  where  it divides  into  three
branches, which are distributed by a great number of  divisions
in the parenchyma of this organ.
   On the outer side it is connected with  the platysma myoides,
the omo-hyoideus, and the  thyroid cartilage, to which it gives
small ramifications,  namely, the laryngeal, which is  directed
towards the upper part  of the larynx, passing between the os
hyoides and the thyroid cartilage into the larynx, to supply the
epiglottis, the muscles, and  the mucous membrane of that
organ.   The crico-thyroid branch is smaller than the pre-
ceding, and descends obliquely over the thyroid cartilage, fur-
nishing ramifications to the  adjacent parts.


           II.   EXTERNAL MAXILLARY  ARTERY.*

   This artery commences at the  anterior part  of the  external

                    * Facial or labial artery. 
OF  THE  ARTERIES.
361
carotid above the lingual,  e; it proceeds  transversely inwards
and forwards, and after describing several curves, gains the inter-
nal part of the angle of the  lower jaw ;  passes  between  the
submaxillary gland  and  the base of the jaw; then ascends
towards the angle of the lips ; enters under  the  union of  the
levator anguli oris and triangularis muscles, and terminates upon
the side of the nose  as far as the inner angle of the eye, com-
municating freely with the nasal twig of the ophthalmic and the
infra-orbitar arteries.


     BRANCHES  OF THE EXTERNAL  MAXILLARY  ARTERY.

   There is beneath the inferior maxilla,  1st, the inferior pala-
tine, which, after arising near the origin of the inferior maxillary
artery, supplies the superior  and lateral  part of the  pharynx,
passes between the pillars of the velum palati, and is distributed
to the pharynx,  the tonsils,  and the  Eustachian tube, commu-
nicating with the superior palatine.   2d, the submental,  which
supplies the mylo-hyoideus  and the digastricus, and  ramifying
above the chin,  sends branches to  the muscles of the superior
hyoid region,  the  submaxillary  gland,  the internal  pterygoid
muscle, and the mucous membrane  of the mouth.   On the face
the external maxillary  artery furnishes  external  and internal
branches, which are distributed to this region.   3d, the coronary
arteries of the lips,  which proceed in a serpentine direction on
the border of the lips, and communicate with each other at  the
angles of the mouth.   4th, the dorsal artery of the nose, which
supplies the muscles, cartilages,  and integuments of  this part,
and is in general the termination of the maxillary  artery.


                III.   THE  LINGUAL  ARTERY.

   This vessel commences at the anterior part  of  the external
   vol. i.                     47 
362
VASCULAR SYSTEM
carotid between the two preceding arteries, passing inwards and
forwards ; it is directed a little upwards, and enters betw een the
hyo-glossus and the genio-glossus as far as the root of the tongue,
proceeding horizontally along its base under  the name of the
ranine artery.  The lingual artery sends branches beneath the
hyo-glossus muscle, and to the middle constrictor of the pharynx,
the thyro-hyoideus, and the digastricus.  From the same point
the dorsal artery of the tongue arises, ramifying  in the back of
the tongue, the tonsils, and velum palati.   Several twigs from
the lingual artery penetrate the genio-glossus muscle ;  and  one
considerable branch, named the sublingual artery, passes  for-
wards above the sublingual gland, furnishing branches  to those
parts, to the mucous membrane of the mouth, and  to the adja-
cent muscles.   Lastly, the lingual artery supplies many bran-
ches under the tongue, which ramify in the substance of  this
organ ;  at the tip, and above the fraenum of the tongue, the two
lingual, which have gained the name of the ranine arteries anas-
tomose  with each other.
POSTERIOR BRANCHES OF  THE EXTERNAL CAROTID ARTERY.

                  IV.   OCCIPITAL  ARTERY.

  This artery,/, commences at the posterior part of the exter-
nal  carotid under the  parotid  gland ;  passes obliquely back-
wards, beneath the posterior portion of the digastricus ; ascends
between  the transverse process of the atlas and the mastoid pro-
cess of the temporal bone, and finally terminates in  a tortuous
manner upon the back part of the head.  The occipital artery
furnishes superior, posterior, and inferior  branches, which  sup-
ply the muscles in that region.  One of them,  which is larger
than the  others, is named  the posterior mastoid artery,  from 
OF THE  ARTERIES.
363
traversing the mastoid foramen, and is subsequently lost on the
dura mater ; others descend in the  substance of the muscles on
the lateral part of the neck.   The extreme branches  are more
superficial, and lose themselves in the  muscles of the posterior
region of the neck.
         V.   THE POSTERIOR AURICULAR  ARTERY.

  This is one of the smallest branches of the external carotid ;
it passes between the  auditory canal and the mastoid process,
and gaining the inferior part of the external ear, divides into two
branches, which are distributed to  the  posterior auricular and
temporal muscles, and the integuments.   But before its division,
it furnishes the stylo-mastoid artery, which enters  the foramen
of the same name, passes through  the  aqueduct of Fallopius,
and supplies the mucous membrane of the tympanum, the semi-
circular canals,  etc.
VI.   INTERNAL  BRANCH  OF  THE EXTERNAL  CAROTID AR-
        TERY,  OR  INFERIOR  PHARYNGEAL ARTERY.

  This artery passes vertically along the lateral and  posterior
part of the pharynx, between the external and internal carotids,
and divides into two branches, namely, the pharyngeal, which
is distributed to the constrictor muscles of the pharynx, and the
meningeal branch, which  passes  between the  internal carotid
artery and the internal jugular vein, and entering the foramen
lacerum posterius, is distributed to the dura mater. 
364.
VASCULAR SYSTEM
BRANCHES  WHICH   TERMINATE  THE  EXTERNAL  CAROTID
                          ARTERY.

                  VII.  TEMPORAL ARTERY.

   The temporal artery, k, separates from the internal maxillary
artery opposite the neck  of the condyle of the jaw, and passes
obliquely upwards beneath the  parotid gland ;  it passes  over
the zygomatic arch, and glides in a tortuous manner  under the
anterior and the superior muscles of the ear and becomes subcu-
taneous, dividing  into three branches, namely,  the  transverse
artery  of  the face,  I, which  ramifies on  Steno's  duct  and
the muscles about this region ;  the anterior auricular  artery,
which supplies the external  ear ;  the middle temporal, which
pierces the temporal aponeurosis near  the zygomatic  arch,  and
is lost in the temporal muscle.   Ultimately,  the temporal artery
divides into the anterior and posterior branches, which  diffuse
themselves over the occipito-frontilis  muscle and the pericra-
nium. 
OF  THE ARTERIES.
365
VIII.   INTERNAL MAXILLARY ARTERY.

              Fipr. 188.
  This  artery is larger than  the  temporal; it commences  at
the external carotid about the same point, and is remarkable for
the great number of important branches which it supplies to the
deep parts of the face.  In this figure the temporal zygoma and
the ramus of the jaw are removed, to show its course  between
the pterygoid muscles to the floor of the orbit, and spheno-max-
illary fossa. 
366
VASCULAR SYSTEM
BRANCHES OF THE  INTERNAL  MAXILLARY  ARTERY  BEHIND
        THE NECK OF THE CONDYLE  OF THE  JAW.


             I.   MIDDLE  MENINGEAL  ARTERY.

   This is the largest branch, a, of the internal maxillary artery;
it mounts almost vertically between the two pterygoid muscles,
and passes into the cranium by the  foramen spinosum of the
sphenoid bone.  It furnishes  branches to the dura mater, the
fifth pair of nerves, and to the aqueduct of Fallopius, and then
divides into the anterior and posterior branches ; the former  is
found in a deep groove of the parietal bone,  and  supplies the
exterior surface of the dura mater ; the latter is  distributed  to
the posterior part of that membrane.
   The ultimate ramifications of  the meningeal artery communi-
cate with those of the opposite side of the dura mater.
II.   INFERIOR DENTAL,  OR INFERIOR  MAXILLARY ARTERY.

  This vessel descends anteriorly along the inner surface of the
ramus of the lower jaw, at the outer side of the pterygoideus
internus, enters the inferior dental  canal, and emerges  by the
mental foramen.   Before entering the dental canal  it supplies
the pterygoid muscle ; in the canal it furnishes the teeth with
branches, which pass through the foramina at their roots.  One
of its branches passes out of the mental  foramen,  is distributed
to the triangularis and quadratus muscles, at b, and communi-
cates with the facial artery ; another branch continues its course
to the chin,  and gives twigs to the canine and incisor teeth. 
OF  THE  ARTERIES.
367
BRANCHES  OF THE  INTERNAL  MAXILLARY  BETWEEN THE
                  PTERYGOID MUSCLES.

         I.   POSTERIOR DEEP TEMPORAL BRANCH.

  This artery, c, ascends between  the  temporal and  external
pterygoid muscles,  and is distributed to the temporal muscle and
periosteum in the temporal fossa.


                II.   MASSETERIC  ARTERY.

  This branch  passes between the temporal  muscle  and the
neck of the condyle of the lower jaw, and ramifies in the mas-
seter muscle, communicating with the transverse artery  of the
face.

                III.   PTERYGOID ARTERIES.

  These arteries, d, are distributed  to the pterygoid muscles.


BRANCHES OF THE INTERNAL  MAXILLARY  ARTERY IN THE
                     ZYGOMATIC FOSSA.

                   I.   BUCCAL ARTERY.

  This artery, i, descends, then advances between the internal
pterygoid muscle and  ramus of the inferior  maxilla, supplying
the buccinator and the zygomaticus major muscles, and the mu-
cous membrane  of the mouth.


         II.   ANTERIOR DEEP TEMPORAL  ARTERY.

  This artery, f, ascends into the anterior part of the temporal
fossa, and is lost in the temporal muscle. 
368
VASCULAR  SYSTEM
                  III.   ALVEOLAR ARTERY.

   This artery descends on the maxillary tuberosity, and sends
branches into the superior and posterior dental canals, to sup-
ply the molar teeth and the membrane of the maxillary sinuses.

                IV.   INFRA-ORBITAR ARTERY.

   This artery,  e, commences from the maxillary at the anterior
superior part of the zygomatic fossa, enters the infra-orbitar ca-
nal, and emerging from it, communicates freely with the facial,
alveolar, buccal, and ophthalmic arteries.

BRANCHES OF  THE INTERNAL MAXILLARY ARTERY IN  THE
                 SPHENO-MAXILLARY FOSSA.

            I.   VIDIAN  OR  PTERYGOID ARTERY.

   This is a very slender artery penetrating the pterygoid canal,
and passing out is distributed  to the Eustachian tube.

           II.   SUPERIOR PHARYNGEAL ARTERY.

   This artery  passes obliquely backwards, and entering the
pterygo-palatine canal, terminates at the phaiynx.


            III.   SUPERIOR  PALATINE ARTERY.

   This artery is larger than the two last mentioned, and  pro-
ceeds vertically into the  pterygo-maxillary fissure, afterwards
into the posterior palatine canal,  and  passing  out is  reflected
forwards to supply the mucous membrane of the palatine arch. 
OF THE  ARTERIES.
369
              IV. SPHENO-PALATINE ARTERY.

  This may be considered as the ultimate distribution of the
internal maxillary artery, which passing into the sphenopala-
tine foramen, supplies the nasal fossa, the maxillary, the sphe-
noidal, and the frontal sinuses.


                INTERNAL CAROTID  ARTERY.

  The internal carotid separates  from the  external behind the
digastric  muscle, mounts between the anterior and lateral part
of the vertebrae of the neck  and the pharynx, and then enters
the carotid canal.  After  emerging from  this  canal it passes
upwards and forwards, penetrates the cavernous sinus of the
dura mater, and  making two inflections, like  the curves  of a
Roman S, arrives beneath the anterior clinoid process; here it
ascends obliquely backwards, pierces the dura mater, and ter-
minates in very many branches.  While the internal carotid  is
in the cavernous  sinus, it sends  two or three twigs  to the dura
mater, the pituitary  body, the membrane  of  the  sphenoidal
sinus, and to the  nerves of the orbit.
VOL. I.
48 
370                VASCULAR  SYSTEM
OPHTHALMIC  ARTERY.

        Fig. 189.
  This artery  enters the  orbit,  traversing  the  optic  foramen
with the nerve/ of the same name, on the outer side of which
it is  situated ;  afterwards  it crosses above it, being covered by
the rectus  superior of  the eye,  g, and  proceeds horizontally
along the internal wall  of the orbit as far as  the internal can-
thus, where it terminates in sending off the following branches:


               I.  THE LACHRYMAL  ARTERY.

  This artery arises from  the ophthalmic immediately after its
entry into the orbit, passes outwards between the external side
of this cavity and external rectus muscle, as  far  as the lachry-
mal  gland, c, where  it ramifies, and  supplies  the  muscles  in
this  region,  as also  the  muscles of the superior and mferior
eyelid.


        II.  THE  CENTRAL  ARTERY OF THE RETINA.

   This artery  is exceedingly  slender; it obliquely  perforates 
OF THE  ARTERIES.
371
the coverings of the optic nerve, reaches its centre, and passes
into the eye, where it sends a great number of branches to the
inner surface of the retina, as  far as the corpus ciliare; one of
its branches penetrates the vitreous humor, and may be traced,
when injected with mercury, to the posterior part  of  the cap-
sule of the crystalline lens.


ARTERIES SENT OFF BY THE  OPHTHALMIC ABOVE THE OPTIC
                          NERVE.

             III. THE SUPRA-ORBITAR  ARTERY.

   This artery passes  forwards along the superior  wall of  the
orbit, and makes its exit by the supra-orbitary foramen, where
it divides into an internal and an external  branch, the  former
supplying the muscles in that region, the  latter extending to
the integuments of the forehead.

          IV.  THE POSTERIOR CILIARY ARTERIES.

   These arteries are very numerous, generally thirty or forty ;
they communicate with each  other round the optic nerve, and
traverse the sclerotica.  The  greater number however of these
arteries, pass between the sclerotic and  choroid coats, and are
distributed to the external  surface of the latter, forming  a very
delicate network.

             V.  THE  LONG CILIARY ARTERIES.

   These arteries are two in number, one on the inner side, the
other on the outer ;  they penetrate the sclerotica, pass forwards
between this coat and the choroid, and arriving at the ciliary
circle,  form by their anastomoses a  network on  the great cir-
cumference of the iris.   From the  inner part of  this arterial 
372
VASCULAR  SYSTEM
 circle other smaller branches proceed, and form a second circle
 within the former ;  and these again  form a third circle of ves-
 sels of greater tenuity, which immediately surrounds the pupil.


  VI. THE SUPERIOR AND INFERIOR MUSCULAR ARTERIES.

   These arteries  are distributed  to  the superior and inferior
 muscles of the eye, to the periosteum of the orbit,  and to the
 lachrymal sack.


 ARTERIES SENT OFF BY  THE  OPHTHALMIC  IN ITS COURSE
         ALONG THE  INSIDE  OF THE OPTIC NERVE.

 VII. THE POSTERIOR AND ANTERIOR ETHMOIDAL  ARTERIES.

   These arteries are directed  towards the internal part of the
 orbit, traverse the posterior internal  orbitar canal, and are lost
 on  the dura mater within the cranium.


 VIII.  THE  SUPERIOR AND INFERIOR PALPEBRAL ARTERIES.

  These  arteries  supply the anterior parts of the  orbit, the
 caruncula lachrymalis, the lachrymal  sack, and the eyelids, and
 communicate  with the lachrymal artery.


 BRANCHES WHICH  TERMINATE THE OPHTHALMIC ARTERY.

                  IX. THE NASAL ARTERY.

  This artery issues  from  the orbit above the tendon of the
orbicularis palpebrarum, passes to the root of the  nose,  and
unites with the terminating branches of  the external maxillary
artery. 
OF THE  ARTERIES.
373
                X.   THE FRONTAL ARTERY.

   This artery passes out of the orbit, and ascends on the  fore-
head, where it is entirely distributed.
   After the internal carotid has given off the ophthalmic artery,
it furnishes the following branches :

       I.   THE COMMUNICATING  ARTERY  OF WILLIS.

   This artery commences from the  internal  carotid after the
ophthalmic, passes backwards and  a little inwards on the side
of the pituitary body and mammillary eminences, and commu-
nicates with the posterior cerebral artery, which is furnished by
the basilar.

       II.   THE  ARTERY OF THE  CHOROID PLEXUS.

   This artery commences above the preceding; it passes out-
wards and backwards near the crus cerebri, penetrates into the
lateral  ventricle, and is distributed to the choroid plexus,

         III.   THE ANTERIOR CEREBRAL ARTERY.

   This artery passes  under the anterior lobe of the brain, e,
Fig. 193, where it  approaches that of the opposite side, and
anastomoses with the communicating artery of Willis.  It sends
off branches to the fornix, the anterior commissure, and the sep-
tum lucidum.   Afterwards the cerebral  artery is directed for-
wards,  turns round the anterior part of the corpus callosum, and
takes the name of that part, terminating on its posterior surface.

             IV.  MIDDLE  CEREBRAL ARTERY.

  This artery passes outwards  and  backwards, and  dips into 
374
VASCULAR  SYSTEM
the fissure of the anterior and middle lobes of the brain, where
it divides into two branches, one for the anterior,  the other for
the middle lobe of the brain.


                    SUBCLAVIAN ARTERY.

                           Fig. 190.
  This artery, a, is so named from its situation  under the cla-
vicle ;  it is situated at the superior part of the chest, and extend-
ing from the arch of  the aorta ; it proceeds under the clavicle,
b, g, and over the middle of the first rib,  passing between  the
anterior and middle scaleni muscles, then runs under  the arch
of the pectoralis minor, /, and enters the axilla, where it assumes
the name of the axillary artery.   The right subclavian arises
from the arteria  innominata, the left separates from the aorta at
the termination of its  arch.   These arteries  give branches di-
rectly upwards,  and directly downwards to the neck, throat, and
chest. 
OF  THE  ARTERIES.
375
BRANCHES OF  THE SUBCLAVIAN  ARTERY.


         I.   VERTEBRAL ARTERY.


                 Fig. 191.
   This artery is the largest branch of the subclavian,  and ex-
tends to the brain.   It arises from the upper and back part  of
the subclavian, a, ascends behind the inferior thyroid artery on
the vertebral column, enters the foramen at the base  of the
transverse processes  of the sixth cervical vertebra, and takes its
course through the canal formed by the  union of the  foramina
of the transverse processes, c, c, c, c,  c, of the other vertebrae of
the neck.  At the dentata,  or  second  vertebra, it leaves this
canal, curving upwards, backwards, and outwards, and perfo-
rates the transverse process of the atlas or first vertebra ;  it then 
376
VASCULAR SYSTEM
 passes between this vertebra and the occiput, forming a second
 curve ; lastly, it enters the skull at the great  occipital foramen
 by the side of the  spinal marrow, and, penetrating the dura ma-
 ter, mounts upwards and forwards between the corpora oliva-
 ria and pyramidalia, as seen in Fig. 193, b, b, uniting with the
 corresponding vertebral artery to form c, the basilar artery.
   The vertebral artery sends off the following branches:
   1.  The posterior spinal artery, which arises near the cor-
 pora pyramidalia,  proceeds downwards and inwards behind  the
 spinal marrow, and is distributed on its  posterior surface as far
 as the second lumbar vertebra.
   2.  The anterior spinal artery, which commences near  the
 termination of the vertebral artery, and descends on  the  ante-
 rior surface of  the spinal marrow.  On a level with the occipi-
 tal foramen it unites with the artery of the opposite side to form
 a common trunk, which descends as far  as the lower  extremity
 of the spinal cord, distributing branches on either side of it, and
 finally communicating with the middle sacral artery.
   3.  The inferior cerebellic artery, which commences at  the
 termination of the  vertebral,  or  sometimes at  the basilar, and
 proceeds in a serpentine course,  distributing numerous  branches
 to the eighth and ninth pair of nerves, to the pia mater, and to
 the fourth ventricle, and to g, the whole inferior surface of  the
cerebellum. 
OF  THE  ARTERIES.
II.  BASILAR  ARTERY.


       Fig. 193.
   The basilar artsry, c, is  formed by  the  union of the two
vertebral arteries, b, b;  it extends along the central groove of
the pons Varolii, and divides into the following branches :
   The  superior cerebellic  artery, which proceeds outwards
and backwards,  and descends on the upper surface of the cere-
bellum, where it spreads out into numerous ramifications.
   The posterior cerebral artery,  which  proceeds downwards
to the posterior  part of the lobes of the brain, divides into very
many branches to supply the different parts of this region, and
receives the communicating branch of Willis, which is given
off by the internal carotid artery.
   vol. i.              49 
378
VASCULAR SYSTEM
              III.  INFERIOR THYROID ARTERY.

  This vessel, Fig. 187, p, commences at the superior part of
the subclavian artery, o :  it extends vertically on the anterior
scalenus as  far as  the fifth vertebra, where it turns inwards to-
wards the thyroid gland, and  sends off internal and external
branches  to  the trachea, oesophagus, longus colli, and  other
muscles in this region ;  a branch, called the ascending cervical,
extends upwards as far  as the rectus anticus major, and is dis-
tributed to the scalenus anticus, the longus colli, and the sple-
nius muscles ; the inferior thyroid artery, at the lower part of
the gland, divides into numerous branches, which supply this
organ,  and  anastomose with  those of the opposite side, and
with those of the superior thyroid artery.
    INFERIOR BRANCHES OF THE SUBCLAVIAN ARTERY.

              I. INTERNAL MAMMARY ARTERY.

  This artery, Fig. 197, e, arises from the subclavian, opposite
the inferior thyroid, passes inwards and downwards in front of
the scalenus anticus muscle, enters the thorax, descends  along
the sterno-costal cartilages, between these and the pleura cos-
talis, and divides into two branches near the ensiform cartilage.
It furnishes several branches  to adjacent muscles, and  after-
wards sends off the following branches :
  The anterior mediastinal artery,  which  descends in the
superior separation of the  anterior mediastinum and  divides
into branches, which  supply  the  thyroid and  thymus glands,
the pleura, and the cellular tissue of the mediastinum.
  The superior  diaphragmatic  artery,  which  accompanies 
OF  THE  ARTERIES.
379
the nerve  of the same name, supplies the fibrous membrane of
the pericardium, the thymus gland, and  the  mediastinum, and
at length is  lost in the fleshy fibres of  the diaphragm.  It also
furnishes external  and internal branches:   the  external sup-
plying the intercostal muscles, the internal passing through
them, and supplying the  muscles of the thorax and abdomen.


            II. SUPERIOR INTERCOSTAL ARTERY.

   This artery, Fig.  196, g, commences  at the lower and back
part of the  subclavian, and descends under the pleura, in front
of the neck  of the first and second ribs, where it generally ter-
minates.  In front of these ribs it sends off a posterior and an
external branch:  the former is distributed  to the  muscles of
the back,  the  latter  to the intercostal muscles, the periosteum
of the vertebrae, the oesophagus, and the bronchi.  In the second
intercostal space  it  furnishes  external  and  internal  branches,
which follow  precisely the same course  as the preceding, and
are distributed to the muscles  or communicate with the first in-
tercostal artery arising from the aorta.


    EXTERNAL BRANCHES OF  THE SUBCLAVIAN ARTERY.

I. TRANSVERSE CERVICAL OR POSTERIOR SCAPULAR ARTERY.

   This artery, o, is directed  transversely outwards, winding
along the scaleni muscles above  the  nerves which form  the
brachial plexus;  then curving obliquely under the trapezius,
the levator  anguli scapulae, and the rhomboideus, it  terminates
at the posterior border of the  scapula, and may be traced to its
inferior angle.  Near its  origin this  artery gives off several
branches, which ascend, and lose  themselves in the muscles at
the side of the neck. 
380
VASCULAR  SYSTEM
             II.  SUPERIOR SCAPULAR ARTERY.

  This artery  commences often at the  preceding or  at the
superior thyroid, takes a tortuous course  behind and beneath
the clavicle, and  arrives at the superior border of the scapula ;
it  afterwards  passes above the  coracoid ligament,  sending
branches  to  the  trapezius, and  ultimately  descends into the
infra-spinatus  fossa, between  the  bone and the infra-spinatus
muscle.


       III.  POSTERIOR  OR DEEP  CERVICAL ARTERY.

   This artery commences  at the posterior part of the subcla-
vian, behind  the anterior  scalenus;   it   passes  between  the
transverse processes of  the two last vertebrae of the neck, and
extends to the great complexus muscle.


                     AXILLARY  ARTERY.

   This artery is  the direct continuation  of the subclavian ; it
is situated at the superior and lateral part  of the  thorax;  and
in the axilla it extends from the  first rib, in the interval of the
two scaleni muscles, as far as  the inferior margin of the tendon
of  the latissimus  dorsi.  The axillary artery  is  seen  in Fig.
190, proceeding under  the clavicle, b, g, and under the arch
formed by the pectoralis minor, h, I.    In the axilla it is sur-
rounded by branches of nerves of  the  brachial  plexus, which
form a sort of sheath for the artery.   The corresponding vein
is  always placed before  the  artery, and it is further protected
by a quantity of cellular tissue and lymphatic glands.  When
it has passed the  anterior edge of the pectoralis  major,  it as-
sumes the name of the brachial artery. 
OF THE  ARTERIES.
381
           BRANCHES OF  THE AXILLARY  ARTERY.

                    I. ACROMIAL ARTERY.

   This artery, h,  commences at the anterior part of the axil-
 lary ;  it descends obliquely towards the deltoid muscle, and  in
 the  narrow space  which  separates this muscle from the great
 pectoral;  it  then  divides into a superior and inferior branch :
 the former ramifies on the shoulder joint, the latter is distributed
 to the deltoid and the great pectoral muscles.


              II.  SUPERIOR  THORACIC  ARTERY.

   This artery, I, generally arises with the former artery, and
 descends between the two pectoral muscles, to which it is dis-
 tributed.


   III. LONG THORACIC  OR  EXTERNAL MAMMARY ARTERY.

   This artery, i, commences a little lower down  than the pre-
 ceding ;  it descends from behind forwards, on the upper  and
 lateral part of the chest, along the inferior margin of  the pec-
 toralis major,  supplying this  muscle, the serratus  magnus, the
 intercostals, the  lymphatic ganglia of  the  axilla,  the integu-
 ments, and the mamma.


                 IV. INFERIOR SCAPULAR.*

  This artery, k, arises from  the inferior part of the axillary,
opposite the inferior border of the tendon of the subscapularis
muscle ; it descends along the lower border of this muscle, and
* Frequently termed the subscapular artery. 
382
VASCULAR SYSTEM
gives off an inferior and superior branch ;  the former supplies
the  serratus  magnus,  the latissimus dorsi, the teres major, and
the integuments ;  the  latter is distributed to the various mus-
cles of the scapula, and to the  articulation of the shoulder.
  V.  POSTERIOR  AND  ANTERIOR  CIRCUMFLEX ARTERIES.

  The former of these arteries,  m, arises  from the  posterior
part of  the axillary, passes backwards,  turns round the upper
part of the humerus, and is lost in the deltoid muscle; the  lat-
ter, n, is generally furnished by  the preceding, and  proceeds
under the  coraco-brachialis and short head of  the biceps; it
turns also round the humerus,  and is distributed to the deltoid
muscle. 
OF THE ARTERIES.
383
BRACHIAL ARTERY.





      Fig. 194.
 
384
VASCULAR SYSTEM
   This artery, a, is a continuation of the axillary ;  it is situated
at the inner and fore part of the arm, and passes  along the in-
ferior edge of the  coraco-brachialis.  About the middle of the
os brachii it crosses over the tendinous attachment  of that mus-
cle, being situated between the fleshy mass of the biceps and
the upper fibres  of the brachialis externus.  This artery then
proceeds behind the inner edge of  the  biceps, descending be-
tween that muscle and the fibres of the brachialis internus ; in
approaching the lower extremity of the os brachii, it is inclined
forwards towards  the  bend of the arm, and lies at i, beneath
the aponeurosis, which is  continued  from the tendon of  the
biceps flexor cubiti.   The brachial artery sends off numerous
branches to the different muscles of the arm,  two of which are
more  considerable than the others, and  are  termed muscular
branches.
   I.  SUPERIOR MUSCULAR BRANCH, OR DEEP HUMERAL.

  This artery, b, commences at the inner side of  the brachial
artery, immediately after it has left the  axilla, passes between
the triceps and  the humerus, accompanied  by the muscular
spiral nerve, and proceeds between  the brachialis externus and
the short portion  of the triceps, then  divides into branches,
which  supply the triceps  near the olecranon and the super-
adjacent  integuments.
           II. THE INFERIOR  MUSCULAR  ARTERY.

  This artery, c, is sent off from the brachial about two inches
lower than the preceding ;  it descends  among the  muscles of
the  inside of the  arm,  and is lost about the  inner condyle, k. 
OF THE  ARTERIES.
385
         III. THE RAMUS  ANASTOMOTICUS MAGNUS.

  This artery, e, commences about two or three inches above
the inner condyle of the os brachii; it  is distributed about the
elbow, and its principal branches communicate with the recur-
rent branches of the .arteries of the fore-arm.
IV.  THE EXTERNAL BRANCHES  OF THE BRACHIAL ARTERY.

  These arteries, /  are small,  and  supply the coraco-bra-
chialis,  the  brachialis  internus, the biceps, and  the integu-
ments.
  The anterior and posterior branches of the brachial artery
are short and slender,  their number is  very  indeterminate, and
they penetrate the muscles, of the front or back  part of the
arm.
VOL. T.
50 
386
VASCULAR SYSTEM
BRANCHES BY WHICH THE BRACHIAL ARTERY  TERMINATES.





                          Fig. 195.
The brachial  artery, a, divides at k,  into three branches 
OF THE  ARTERIES.
387
1st, the radial, n, o;  2d,  the ulnar, 1; and 3d,  the interos-
seous artery, m;  the last two, however, generally arise by one
trunk, as at I, in  this figure.*


                   THE RADIAL ARTERY.

  This artery is  situated at the anterior and front  of the fore-
arm : it follows the direction of the brachial artery, a, and at
the bend of the  arm, k, separates at an acute angle from the
ulnar.   The radial artery extends from  the upper extremity of
the radius,  k, as  far  as the articulation  of the carpus, o, here it
turns outward, passes between  the  two first metacarpal bones
into the palm of the  hand, where it  forms the deep palmar
arch, p.  But it is  important more particularly to understand
its relative  connexions.  Above, it lies between the pronator
teres and the supinator longus,  and about the middle of the
fore-arm passes  over  the  lower attachment of  the pronator
teres, continuing  its  course between the supinator longus and
the flexor carpi radialis, accompanied by a branch of  the mus-
culo-spiral  nerve.   At  the  lower  extremity of  the radius it
divides into two branches, which are distributed to the hand.
  The branches  of  the  radial  artery, in its course  along  the
fore-arm are as follows :
   1. The radial recurrent,  which passes  outwards  and  up-
wards near the elbow, and is  distributed to the outer condyle,
where  it anastomoses  with  branches  of the brachial.   See
Fig. 194.
  2. The internal  branches,  which are  very numerous, are
distributed to the muscles of the anterior  and superficial layer
of the fore-arm.

  * The division of the brachial artery is  not  always at the same point.  I
have not unfrequently observed  it  about the middle of the arm,  and som«-
times as high as the  axilla. 
388
VASCULAR SYSTEM
  3.  The superficiales vola, Fig. 194, h, which descend upon
the anterior annular ligament of the wrist, distributing a num-
ber of twigs to  the  muscles and integuments of the palmar
region.
   4.  The  radial artery at the back of the wrist is only cover-
ed by the tendons  of the abductor pollicis longus, the exten-
sores  pollicis, and the integuments,  and ramifying on the back
of the hand, is named the dorsal artery of the wrist.
   5.  The dorsal artery of the metacarpus passes immediately
over the second metacarpal  bone, descends on the back of the
hand, and is sometimes prolonged to the fore-finger.
  6.  Small vessels supply the back part of the thumb, termed
the dorsal arteries of the thumb.
  On entering into  the palm of the hand, the radial artery
divides into two branches :
   7.  The  artery of the thumb, which supplies a branch to the
outer edge of the fore-finger.
   8.  The  deep palmar arch, p, which is obvious in the pre-
ceding  figure, passes  transversely  from  the thumb over the
metacarpal  bones, and terminates  by anastomosing  with  a
branch of the ulnar  artery.    The  deep palmar arch furnishes
twigs to the interosseous muscles, and to the deep-seated parts
of the palm of the hand.
                   THE ULNAR ARTERY.

   This artery, /, is larger than the radial;  it is situated at the
anterior and inner part of  the fore-arm, and extends from the
bend of the arm as far as the palm of the hand.   It  takes its
course under  the pronator teres, the flexor carpi radialis, the
palmaris longus, and the flexor sublimis perforatus,  but  passes
over the flexor profundus perforans.   It descends between the 
OF THE  ARTERIES.
389
two last-mentioned muscles, and is  found on the ulnar edge of
the arm, at the outer edge of the flexor carpi ulnaris ;  it  then
proceeds over the annular ligament  of the wrist, and under the
palmar aponeurosis, until it  arrives  at the metacarpal bone of
the little finger, where it forms the superficial palmar arch, seen
in Fig. 194, g.
  The branches  given off by  the ulnar  artery  in its course
along the fore-arm and wrist, are the following :
  1. The anterior and posterior recurrent arteries arise  from
the ulnar artery, immediately below the elbow.   The anterior
is distributed to the fore part of the inner condyle, the posterior
to the back part of the same  process of bone.  These arteries
communicate with branches of the brachial.
  2. The ulnar artery  furnishes numerous branches to  the
muscles of the  fore-arm.
  3. The anterior  and  posterior  interosseous  arteries :  the
former, Fig. 194,  at I,  descends in front of the interosseous lig-
ament, between the flexor longus pollicis and flexor profundus
perforans,  and arriving at the edge  of the  pronator quadratus,
m, passes between the radius and ulna  to the back part of the
arm, and spreads its extreme  branches on the wrist and back
of the hand.  The latter, or posterior interosseous artery, after
traversing  the interosseous  ligament beneath  the anconeus,
sends off the interosseous recurrent,  which ramifies on the back
part  of the elbow joint, and  extends between  the supinator
brevis and abductor longus pollicis  manus, and afterwards be-
tween the two layers of the  posterior muscles  of the fore-arm
as far as the wrist.
  4. The superficial palmar arch, Fig. 194, g, is a continua-
tion of the ulnar artery, and  is situated above the tendons of
the flexor sublimis perforatus, immediately  beneath the palmar
aponeurosis;  it commences  at  the inner side  of the hand,
crosses the metacarpus, and terminates at the root of the thumb 
390
VASCULAR SYSTEM
by branches which unite with  the radial artery.   The con-
vexity of the arch  is turned towards the fingers, and furnishes
the collateral branches of the fingers, namely —
  1.  A  branch to the  muscles and inner  edge of the  little
finger.
  2.  The first digital artery, which furnishes two branches,
one to the outer side of the little finger, the other, to the inner
side of the ring finger.
  3.  The second digital artery, which in a  similar  manner
furnishes branches  to the outer edge of the ring finger, and to
the  inner side of the middle finger.
  4.  The  third digital  artery, which  is  distributed to  the
outer edge  of the middle finger, and  to the inner edge of the
fore finger.
  5.  The ramus pollicis ulnaris, or last branch of the ulnar
artery, which supplies the muscles of the thumb. 
OF THE  ARTERIES.
391
ARTERIES  FURNISHED  BY THE THORACIC AORTA.

                     Fig. 196.
BRONCHIAL ARTERIES.
  There are generally two  bronchial arteries, a, b, one on the
right side, the other on  the  left;  they are  distributed  to the
bronchi, and ramify in the pulmonary tissue. 
392
VASCULAR SYSTEM
                  OESOPHAGEAL  ARTERIES.

  These arteries vary in number from  two  to five  or six, and
curving to the right and left ramify on the oesophagus.
            POSTERIOR  MEDIASTINAL  ARTERIES.

  These arteries are very numerous, and ramify  in  the poste-
rior mediastinum and on the aorta.
             INFERIOR INTERCOSTAL  ARTERIES.

   There  are  nine or ten inferior intercostal arteries on each
side ; these commence at the posterior lateral part of the aorta;
they pass over the bodies of  the  dorsal vertebras to the poste-
rior extremity of the ribs, and entering the intercostal spaces
each artery divides into two branches, a dorsal and an inter-
costal; the former penetrates the vertebral canal by the inter-
vertebral foramen, and ramifying  on the spinal marrow, passes
out between the transverse processes to the dorsal and lumbar
muscles;  the  latter, which  is the largest branch, proceeds in
the intercostal  space beneath the pleura, and divides into an
inferior and a superior branch.  The  inferior intercostal arte-
ry proceeds along  the superior edge of the rib which is beneath
it; the superior intercostal passes along a groove in the infe-
rior edge of the rib above it; but towards  the sternal end of
the rib  it is situated in the  middle of the  intercostal space.
The intercostal arteries  terminate in  front of the  thorax by
communicating with the internal mammary. 
OF  THE  ARTERIES.
393
   ARTERIES  FURNISHED  BY  THE  ABDOMINAL  AORTA.

      THE RIGHT INFERIOR DIAPHRAGMATIC ARTERY.

  This  artery  generally arises from  the aorta by itself, some-
times with the left, and occasionally from the  cceliac artery.
It ascends on the outer side  of the right pillar of the diaphragm,
and divides  into two branches, which pass between  the liver
and diaphragm, supplying the right part of the diaphragm, and
giving two or three branches to the surrenal capsule.
         LEFT INFERIOR DIAPHRAGMATIC ARTERY.

  This  artery,  which  arises  with  the  preceding,  furnishes
branches to the left pillar of the diaphragm, the oesophagus, the
surrenal capsule, and finally  ramifies  on  the phrenic centre
of the diaphragm, Fig. -01, a.
                     CffiLIAC  ARTERY.

  This  artery is large and short, and is situated  between the
small lobe of the liver (the lobulus Spigelii) and the small cur-
vature of  the stomach ;  it proceeds at a  right angle from the
abdominal aorta, between the pillars of the diaphragm ;  oppo-
site the last dorsal vertebra it passes horizontally forwards and
divides into three branches, namely, the coronary artery of the
stomach, the  hepatic and the splenic arteries.   The cceliac
artery is seen in Fig. 201, e.
  VOL.  I.                 51 
394
VASCULAR SYSTEM
I.  CORONARY ARTERY OF THE  STOMACH.

                Fii. 197.
   This artery, h, follows the small curvature of the stomach as
far as  the  pylorus, where  it  communicates with the  pyloric
artery.  It furnishes —
   The oesophageal branches,  which arise near the cardia, and
ascend upon the oesophagus. 
OF THE  ARTERIES.
395
  The gastric branches, c, which originate at the  small  cur-
vature  of the stomach, and  pass over  the  surface of a, this
organ.
  Frequently the coronary  artery  sends a very considerable
branch to the liver.

                  II. HEPATIC ARTERY.

  This artery, I, is much larger than the preceding, and directs
itself transversely to  the right and under the lobulus Spigelii as
far as the neck of  the gall-bladder ;   it furnishes  the following
branch3s :
  The pyloric artery, which is  found on the right side of the
pylorus, c; passing from right to left along the small curvature
of the stomach,  communicating with the stomachic coronary
branch, and  ramifying on  the  surface of the  stomach  and
pylorus.
  The right gastro-epiploic artery, e, e, which  arises  on the
right beneath the pylorus, and descending vertically behind the
stomach, it passes  from right to left  along its greater curvature
in the  anterior lamina of the great omentum, i, i, i, and unites
with the  left gastro-epiploic artery:  in  Fig. 198, it  is  seen
giving  branches  to the stomach, i, the  duodenum, c, and pan-
creas, d.
  After furnishing these  branches, the hepatic artery proceeds
towards the  right  side in front  of the vena porta, behind the
hepatic duct, to  the right side of the lobule of the liver, where
it divides into two branches.
  The right branch furnishes the cystic artery, which supplies
the  parietes of the gall-bladder, d, dips into the fissure of the
liver, and ramifies  in the right lobe.
  The left branch penetrates by the same fissure  of the liver,
and is distributed to the  left  lobe and the lobulus Spigelii, ac-
companying the  divisions of the vena porta. 
396
VASCULAR SYSTEM
II.  SPLENIC ARTERY.
   In this figure the stomach and  liver are turned  up to shew
the pancreas and spleen.  The  splenic artery, e, at  its com-
mencement proceeds  from the right to the left, forming several
inflexions along the upper part of the pancreas, d, as far as the
fissure of the spleen,/.   In this course it furnishes —
   The pancreatic branches, which supply the pancreas, d.
   The left gastro-epiploic branch, which ascends a  little to
the left towards the great extremity of the stomach, and  then
descends along the great  curvature, at the middle of which, at
g, it communicates with  the corresponding artery of the right
side.
   At a little  distance  from the spleen, /  the splenic artery
divides into five  or  six branches, which penetrate this organ
after furnishing —
   The vasa brevia, which are short branches  passing from the
divisions of the splenic artery, and are distributed to the large
extremity of the stomach. 
OF  THE  ARTERIES.                397
SUPERIOR MESENTERIC ARTERY.


            Fig. 199.
  This artery, a, commences at the anterior right  part of the
aorta a little below the cceliac, and passing downwards behind
the pancreas and before a portion  of the  duodenum, it gains
the upper  part  of  the mesentery, between the two folds of
which it enters, and passing from left  to right forms a curve, the
convexity of which is turned to the left and forwards.  It ter- 
398
VASCULAR  SYSTEM
minates at the end of g, the ilium, communicating with d, the
inferior right colic artery.   It furnishes the following branches :
   1st. The superior right  colic artery, b, which supplies the
arch, and left side of the colon, /,  where that intestine begins
to run over the kidney.
   2d. The  middle right  colic artery :  this branch,  h, pro-
ceeds  to  the right,  and a little  upwards  in the  mesocolon
divides, and  on the right side communicates with the  superior
right colic artery, and  on the  lower side furnishes fifteen or
twenty branches, which, after frequently communicating in the
form of arches, proceed to the right side of the colon.
   The inferior right colic,  d, or ilio-colic artery, which  passes
downwards  to  supply the  caput coli, and  the last portion of
the  ilium.   Its  branches  communicate  with the descending
branch of the middle right colic artery and with  the extremity
of the superior mesenteric artery itself.*
BRANCHES  WHICH  ARE  FURNISHED  ON  THE  LEFT SIDE
          OF  THE SUPERIOR  MESENTERIC ARTERY.

   The convexity  of this  artery sends  off fifteen  or twenty
branches, c, c, which proceed obliquely downwards, divide into
small twigs there, and unite with each other very frequently in
the form of arches.  From these primary arches smaller twigs
commence, which divide in the same manner,  and constitute
secondary arches by communicating similar to the first.  These
secondary arches in like manner produce twigs in a  third series
of arches  ; from these again a  fourth and fifth series  of minuter
arterial arches may  be traced to the border of the intestine,

  * Although this artery is generally named as a branch immediately issuing
from the superior mesenteric, yet it more commonly proceeds from the supe-
rior right colic;  it is therefore represented as such in this figure. 
OF THE  ARTERIES.
399
where they appear as a network, which finally ramify  and sub-
divide to infinity over the surface of the small intestines, g, g,
and supply the muscular and mucous coats.   The distribution
of this artery on the valvulae conniventes is very apparent when
these vessels are filled with fine injection.
   The distribution  of the several branches  of  the superior
mesenteric artery is seen also in Fig. 200, a, b, / h, i, k. 
400
VASCULAR  SYSTEM
THE INFERIOR  MESENTERIC ARTERY.

               Fio;. 200.
   This artery commences at the anterior part  of the aorta, c,
it descends a little to the left, enters the iliac mesocolon, and
is extended to the rectum as far  as  the anus.   It furnishes the
following branches :
   1st.  The  superior left  colic  artery,  e, which  extends  to 
OF THE  ARTERIES.
401
the left side of the colon, and communicates  with  the  left
branch of the right colic artery,/
  2d.  The  middle left  colic  artery,  o, which is generally a
branch of the preceding ; its distribution  to  the colon, p, p,  is
obvious in the figure.
  3d.  The inferior  left colic artery, which proceeds towards
the sigmoid flexure  of the colon,  and divides into two bran-
ches, d, g.
  The left colic arteries are  arranged precisely  the same as
those of the right  side ;  namely,  after  forming arches  and
areolae, they supply the coats  of the  intestine.
  When the inferior mesenteric artery arrives at the posterior
part of the  rectum,  it  divides  into the superior  hamorrhoidal
arteries, which descend along the posterior surface of this in-
testine, and  communicate with the middle and inferior haemor-
rhoidal arteries.
 ARTERIES  WHICH  ARE  FURNISHED  LATERALLY BY THE
                    ABDOMINAL AORTA.


                   SURRENAL ARTERIES.

  There is one  of these arteries on  each side; they arise a
little above the  renal, pass  transversely across the vertebral
column, and are distributed to the surrenal capsules, marked c,
in Fig. 201.
VOL. I.
52 
402
VASCULAR  SYSTEM
RENAL OR EMULGENT ARTERIES.

             Fig. 201.
  These arteries are of  a  large size, and very short; there is
one on each  side;  they pass off from the aorta  at / trans-
versely across the vertebral column, and arriving at the kidney, 
OF  THE  ARTERIES.
403
d, divide into two, three, or  four branches, which enter be-
tween the pelvis of the ureter and the renal vein.


                  SPERMATIC ARTERIES.

   These arteries, g, are two in number, very slender, and  of
considerable length ;  they commence at the anterior or lateral
parts of the aorta, and sometimes from the renal; they descend
on the sides of the vertebral column, in front of the psoas mus-
cles, and ureters, n, and accompany the  spermatic  veins.  In
the male, — they pass out by the inguinal ring, and sending
some  branches  to the  spermatic cord, they terminate in the
epididymis and  the testis.  In the female, — they pass to the
ovary, to the Fallopian  tubes, the round  ligament,  and the
sides of the uterus.
                    LUMBAR ARTERIES.

  There are commonly four or five of these arteries on each
side, which commence at the back part of the aorta, and are
distributed to the spinal canal, the peritoneum, the muscles of
the loins, and to the sides of the abdomen and pelvis. 
404
VASCULAR SYSTEM
THE ARTERIES  WHICH  TERMINATE  THE AORTA BELOW.

               MIDDLE  SACRAL  ARTERY.

                        Fig. 202.
  At the fourth lumbar vertebra  the aorta divides, Fig. 201,
at i, into the primitive iliacs ;  and the middle sacral artery, o,
commences at the back part of this  division, and  descends
along the  anterior surface of the sacrum, and terminates near
the summit of the os coccygis : in the annexed figure this ves-
sel is marked a.

                     PRIMITIVE ILIACS.

  These  vessels, b, c, are formed by  the  bifurcation  of the 
OF THE  ARTERIES.
405
aorta.   Separating from each other at an acute angle, they de-
scend along the edge of the psoas muscle as far as  the sacro-
iliac articulation, where they divide  each into the external and
internal iliac arteries.   The  course  of these  vessels  is  very
obvious in the figure preceding.
        INTERNAL  ILIAC OR HYPOGASTRIC ARTERY.

  This  artery dives almost vertically into  the  pelvis, in front
of the sacro-iliac articulation ;  and after a short course divides
into a great number of branches.
       BRANCHES OF THE INTERNAL ILIAC ARTERY.

                  I. ILIO'LUMBAR ARTERY.

  This artery  proceeds  from the internal iliac, opposite the
base of the sacrum ;  it  varies much  in size, and ascends out-
wards  and backwards, under  the  psoas  muscle, then  divides
into  an ascending and  a transverse branch, which are dis-
tributed to the lumbar muscles.
            II.  THE LATERAL SACRAL ARTERY.

   Sometimes  there  are  two  of these  arteries on either side 5
these vessels descend in front of the anterior sacral foramina, as
far as the os coccygis.   They furnish  external and internal
branches: the former enter the sacral canal, and ramifying on
the membrane which lines it, they pass out, and are lost on the
muscles at the posterior part of the sacrum ; the latter, ramify
in the sacral nerves and ganglia, and in the pyramidalis muscle. 
406
VASCULAR SYSTEM
III. GLUTEAL OR  POSTERIOR ILIAC  ARTERY.

                  Fig. 203.
   This is the largest branch of the internal  iliac ; it descends
outwards and backwards, and  passes out of the  pelvis through
the sacro-sciatic notch, above the pyriformis muscle;  it then
proceeds to  the posterior  part of the  pelvis, covered  by the
gluteus maximus,  and  divides into two branches:  the super-
ficial  branch, c, is distributed  to  the gluteus  maximus  and
medius and the sacro-sciatic ligament;  the deep-seated branch
a, b, ascends between the  gluteus medius  and minimus, and is 
OF THE  ARTERIES.
407
distributed to the muscles of this region, and to the capsule of
the hip-joint.


                  IV. UMBILICAL  ARTERY.

   This artery passes obliquely forwards and inwards, as far as
the superior lateral part of the bladder, from whence it ascends
behind the anterior parietes of the abdomen to  the umbilicus.
In the adult, this artery is almost obliterated ; but in the foetus,
it appears to be a continuation of the internal iliac, and passes
out by the umbilicus to form a part of the umbilical cord.
                  V. VESICAL  ARTERIES.

  These arteries present many variations in number and origin ;
they arise from  the umbilical, middle  haemorrhoidal, internal
pudic, and obturator arteries.   The internal iliac furnishes a
considerable branch, which supplies the fundus of the bladder,
commencement  of the  urethra,  prostate gland, the  vesiculae
seminales, and vas  deferens ;  the ultimate ramifications reach
to the rectum.
                 VI.  OBTURATOR ARTERY.

  This artery generally commences at the internal iliac, or the
gluteal, and sometimes from the epigastric ;  it proceeds to the
obturator muscle, and advances as far as the obturator foramen,
the superior part of which it traverses ;  it  issues from the pelvis
through the space left by the obturator membrane, and divides
into two  branches, which are  distributed  to  the hip-joint, and
to the muscles on the inside of the thigh. 
408
VASCULAR  SYSTEM
           VII.  MIDDLE HEMORRHOIDAL ARTERY.

  This artery descends obliquely  on the anterior part of  the
rectum ;  it supplies the tunics of this intestine, and communi-
cates with the superior and inferior haemorrhoidals.


                   VIII. UTERINE ARTERY.

  The size of this  artery is always in relation to the develope-
ment of  the uterus ;  arising from  the internal iliac, or internal
pudic, it passes  upon the  broad ligament, and is distributed to
the lateral and inferior parts of the uterus.


                   IX.  VAGINAL ARTERY.

  This vessel is not constant in its origin, for it commences  at
the internal pudic,  the middle haemorrhoidal, or the umbilical
artery ; it proceeds to the vagina  and external parts of gene-
ration.

                   X.  ISCHIATIC  ARTERY.
  This vessel appears to be a continuation of the internal iliac
artery ; after supplying the rectum and bladder, it descends in
front of  the pyramidalis muscle, it proceeds through the great
sciatic notch, and at its  exit from the pelvis divides into nume-
rous branches, which supply the gluteus maximus, the levator
ani, the sciatic nerve, and the muscles  of the posterior crural
region.

               XI.  INTERNAL PUDIC ARTERY.

  This artery  is smaller than the ischiatic, and  is frequently
furnished by it.   It descends  before the sciatic plexus and the 
OF THE  ARTERIES.
409
pyriformis muscle, and issues from the pelvis by the lower parts
of the sciatic notch,.between the pyriformis and posterior bor-
der of the levator ani; it afterwards proceeds  between the two
sacro-sciatic ligaments, to the internal surface of the ischium, as
far as the common  attachment of the  ischio-cavernosus  and
transversus perinaei, and here divides into two branches, which
take a different course in the male and  in  the female, and of
which one is inferior, the other superior.
   1st.   The inferior branch, or perineal artery, proceeds be-
tween the integuments and  transversus perinaei, as far as the
lower part of the scrotum, and is distributed to the muscles of
the perinaeum ; some branches pass towards the rectum, termed
the inferior hamorrhoidal arteries.  The inferior branch after-
wards penetrates the septum scroti,  and supplies  the  integu-
ments of the genitals.
   2d.   The superior branch ascends above the transversus pe-
rinaei, along the ascending branch of the ischium, and the ramus
of the pubis to the symphysis of this latter bone, where it  di-
vides into two branches, the dorsal artery of the penis, and the
artery of the corpus cavernosum.
   3d.   The transverse artery of the perinaum is furnished  by
the superior branch of the internal pudic, near the origin of the
latter ; it passes above the transversus perinaei  muscle, and sup-
plies the bulb of the urethra.
   4th.  The artery of the corpus  cavernosum passes into  the
cavernous body, and divides into a great number of branches to
supply its tissue.
   5th.  The dorsal artery of the penis, Fig. 204, / supplies
the fibrous membrane of the corpus cavernosum, and terminates
in the glans penis.
   In the female, the inferior branch of the internal pudic artery
terminates in the external labia ; the superior is distributed  to
the clitoris and orifice of the vagina.
   vol. i.            53 
410
VASCULAR  SYSTEM
                 EXTERNAL  ILIAC ARTERY.

   This vessel, b, d, is formed by the bifurcation of  the primi-
tive iliac artery ; it extends to the crural arch, where it takes
the name of femoral artery.  The  external  iliac  descends ob-
liquely outwards, along the inner and  fore  part  of  the psoas
muscle, having on its inner side the external iliac vein.  It fur-
nishes the following branches : —
               1.   THE EPIGASTRIC  ARTERY.

   This artery proceeds from the inner side of the external iliac,
at e, about an inch before it passes into the  thigh  ; it  extends
inwards and a little forwards, behind  the  spermatic cord,  the
direction of which it crosses towards the external border of the
rectus abdominis muscle   About two inches  above the pubis
it is situated on the posterior surface of this muscle, and termi-
nates by several twigs at the umbilicus.   Its distribution may
be seen in Fig. 201, I.
              II.   CIRCUMFLEX ILIAC  ARTERY.

   This vessel, Fig. 202, / commences at the outer part of the
iliac artery, and ascends obliquely outwards along the external
border of the iliacus muscle, as far as the anterior  superior spi-
nous process of the ilium ;  it then passes backwards, and divides
into two branches :  its external branch supplies  the transversa-
lis and the internal oblique muscles; its internal branch follows
the line of the crista ilii, and  terminates in the  same muscles.
In the .subsequent figure it is marked b. 
OF THE ARTERIES.
411
FEMORAL ARTERY.





    Fig;. 204.
mi.   . 
412
VASCULAR  SYSTEM
   Immediately the external iliac artery has emerged from under
the crural arch at c, it assumes the name of femoral: it com-
mences at the middle of the space which separates the anterior
superior spine of the ilium from  the pubis ;  it descends on the
anterior and internal part of the psoas muscle, and upon the ex-
ternal femoral vein ; towards the lower part of the thigh it en-
ters the aponeurotic sheath of the triceps adductor magnus, m,
on its exit from which it takes the name  of popliteal artery.
To the surgeon, an acquaintance with the femoral artery is of so
much importance that its relative situation claims further notice.
   Anteriorly, the femoral artery is connected with  the crural
aponeurosis, the integuments, and the inguinal lymphatic glands ;
it is situated in a triangular space, bounded above by the crural
arch, on the outer side by the sartorius, and on the inner  side
by the middle adductor and the vastus internus.   Farther down
it is covered by the sartorius muscle, which crosses its direction.
Posteriorly, it is situated upon the pectineus and the middle ad-
ductor muscles.
   On the outer side it is connected at first to the crural nerve ;
then to the tendon of the psoas and the iliac muscles ; and lastly,
it is placed upon the inner portion of  the triceps, which sepa-
rates  it from the shaft  of the femur.
  On its inner side, it  is  in contact with the femoral  vein  and
the pectineus  muscle,  and at the lower  part of the thigh it  is
concealed by the sartorius muscle.


      INTERNAL BRANCHES OF  THE  FEMORAL ARTERY.

               I.   EXTERNAL  PUDIC ARTERY.

  These vessels are two  in number :  one superficial, c, which
commences near the crural arch, proceeds transversely inwards,
and divides into branches, which are lost in the integuments of
the inferior part of the  abdomen, the penis, /,  and the labia in 
OF THE  ARTERIES.
413
the female ; the other is a deep-seated branch, distributed under
the crural aponeurosis.

     EXTERNAL BRANCHES OF  THE  FEMORAL ARTERY.

           II.   SUPERFICIAL MUSCULAR ARTERY.

   This artery commences nearly on a level with the profunda;
it passes transversely outwards between  the sartorius and  rec-
tus, and divides into ascending and descending branches, which
supply the muscles and integuments of the upper  part  of the
thigh.  See Fig. 203, o.

     ANTERIOR BRANCHES OF  THE  FEMORAL ARTERY.

   ABDOMINAL SUBCUTANEOUS,  OR EXTERNAL EPIGASTRIC
                         ARTERY.

   This is a very small artery ; it commences immediately above
the crural arch, and ascends between  the abdominal aponeuro-
sis and the integuments, as far as the level of the umbilicus.
   The other anterior branches of the femoral artery are  very
small, and are distributed to the cellular tissue of  the integu-
ments.

     POSTERIOR BRANCHES OF  THE FEMORAL ARTERY.

ARTERIA PROFUNDA FEMORIS,  OR  DEEP MUSCULAR ARTERY.

   This vessel, h, is nearly as large as the femoral artery itself;
it commences about  two  inches below the crural arch ; it de-
scends backwards between the adductor  muscles  and internal
portion of the triceps, as far as the middle of the thigh.  It then
diminishes in size, passes through the aponeurosis of the adduc-
tor longus to the back part of the  limb, and terminates in 
414
VASCULAR  SYSTEM
two branches, which enter into  the short portion of  the biceps
femoris and the semimembranosus  The deep muscular artery,
which we have just described, furnishes the following branches:
   1.  The external circumflex artery, n, which commences at
the outer side, passes outwards behind  the sartorius and rectus
femoris, and divides into two branches ; the one is distributed to
the parts above the hip joint, the other descends in the  fore
part of the thigh  between the triceps extensor and the rectus
femoris, in which it ramifies.
   2.  The internal circumflex  artrry,  which is larger than the
preceding,  passes backwards between the pectineus and the ten-
dons of the  psoas and the iliac muscles, then  divides into  two
branches, one of which supplies the muscles at the neck of the
femur, the other is  distributed to the flexors of the leg.
   3.  The superior perforating artery.
   4.  The middle perforating artery.
   5.  The inftrior perforating artery.*
   These vessels comprehend all the great muscular branches of
the profunda, except the two circumflex arteries ; they vary in
number, and are proportioned in  size  to the bulk of the limb.
These arteries perforate the adductors and proceed to the back
part of the thigh.   A particular  knowledge of the distribution
and branches of the perforating arteries is really unattainable,
for they ramify in every direction, supply all the large mass of
muscles on the back part of the thigh, and communicate freely
with the sciatic, the  gluteal, and the  obturator arteries.   A
branch of the middle perforating artery penetrates into the femur
by the nutritious canal which we observe on the linea aspera of
that bone.

  * These arteries are irregular in place, size,  and numher; they are  fre-
quently named numerically, as the 1st, 2d, 3d, and sometimes branches are
termed the 4th and 5th  perforating arteries. 
OF THE  ARTERIES.                415
POPLITEAL ARTERY.
Fis. 205.
  This vessel, a, is a direct continuation of the femoral arteiy,
the latter merely changing its name after it has perforated the 
416
VASCULAR SYSTEM
adductor magnus ; it descends into the  ham  between the con-
dyles of the femur, and extends from the commencement of the
inferior third of the thigh to the superior fourth of the leg.  On
the back part it  is connected with  the sciatic nerve,  the  popli-
teal vein, and the semimembranosus ; afterwards, and more in-
feriorly, with the gastrocnemius, the  soleus, and the  plantaris;
it is separated above  from the femur by a quantity of adipose
tissue ; farther down it rests upon  the back of the knee  joint;
and below upon the popliteus and the  tibialis  posticus mus-
cles.   The popliteal artery, after giving off a number of small
branches to the neighboring parts,  divides  into three principal
branches to supply the leg.


          BRANCHES OF  THE POPLITEAL ARTERY.

  There are three superior articular arteries  arising from  the
popliteal in the ham.
  1.   The internal superior articular arteries, e,f: there are
generally two or three of these vessels, which vary much ; they
descend inwards, pass under the  tendon of the  long adductor,
proceed on the internal part of the femur above the condyle,
and are distributed into the triceps muscle and the articulation
of the knee.
  2.   The external superior articular  artery,  b,  passes out-
wards, turns on the external part of the femur above the con-
dyle,  and divides into two branches, the  superior of which is
lost in the triceps ;  the inferior descends on the external condyle
of the femur.
  3.   The middle superior articular artery proceeds from the
anterior part of the popliteal to supply the cellular and adipose
tissue posterior to the crucial ligaments of the articulation of the
knee.
  These and the following branches are given off by  the  popli-
teal to the upper part of the leg.   The  arteries just named are 
OF THE  ARTERIES.
417
distributed to the posterior surface, and dive into the substance
of the  gastrocnemii  muscles, terminating in  the soleus,  the
popliteus, and plantaris.
  There are two inferior articular arteries, which arise from
the popliteal at the superior part of the leg, namely,
   1. The  internal inferior  articular artery,  g, which  de-
scends immediately behind the internal tuberosity of the tibia,
to the internal part  of the  ligamentum patellae, ramifying on
the articulation of the knee and the  periosteum of the tibia.
  2. The  external inferior  articular artery,  c, which  de-
scends lietween  the  popliteus and gastrocnemius, then passes
under the tendon of the biceps and external lateral  ligament,
and is distributed to the articulation of the knee, the ligamen-
tum patellae, and parts in this region.
  The  popliteal  artery having  given off these arteries,  de-
scends behind  the popliteal muscle, and divides into  the ante-
rior tibial, the  peroneal, and the posterior tibial arteries.
VOL. I.
54 
418
VASCULAR  SYSTEM
ANTERIOR  TIBIAL ARTERY.




          Fig. 206.
The anterior tibial artery, b, at its commencement is direct- 
OF THE  ARTERIES.
419
ed horizontally forwards; it passes from the ham  between  the
inferior edge  of the popliteus and the superior  fibres of  the
soleus, then proceeding through  the upper extremity  of  the
tibialis posticus and a perforation in  the interosseous ligament
to arrive at the  fore  part  of the leg ; the artery  afterwards
passes downwards upon the interosseous ligament, between  the
tibialis anticus and the extensor proprius pollicis, c; below  the
middle of the  leg it advances more forward, crosses under  the
tendon of the extensor proprius pollicis, and is situated between
that tendon and the tendon of the extensor longus digitorum,
e ;  at the ankle it is extended over the front of the tibia ; then
having passed  under the anterior annular ligament  of the instep
at d, it assumes the name of the dorsal artery of the foot.  The
posterior tibial artery furnishes the following branches:
   1. The recurrent artery of the knee, which passes upwards
and inwards, supplies the upper  extremity of the tibialis  an-
ticus, and is lost in the articulation of the  knee, a, and the in-
teguments.
   2. Numerous small branches to the muscles on  the fore part
of the leg.
   3. The internal malleolar  artery, which  ramifies over  the
inner ankle.
   4. The external malleolar artery,  which  ramifies over  the
outer ankle.
              DORSAL ARTERY  OF THE FOOT.

  This  artery, d, is  the direct continuation of the  anterior
tibial, and extends over  the  upper surface of the foot to the
posterior extremity of the first metatarsal bone, where it de-
scends into the sole of the foot,  by passing through the abduc-
tor of the second toe.   It distributes  numerous but  very slen-
der external and  internal branches, to supply  the adjacent 
420
VASCULAR  SYSTEM
parts  of the foot.   Two of these branches have been named
the tarsal and metatarsal  arteries ;  these cross  the  tarsal and
metatarsal bones, and pass  obliquely  to  the outer edge of the
foot.
   The  interosseal arteries come off from  the tarsal or meta-
tarsal, and supply the  interosseous spaces and superior surface
of the toes.
   A considerable branch proceeds from the dorsal artery  of the
foot, along the space between the two first metatarsal bones,
and divides into,
   The  dorsal artery of the great toe, and an artery which is
extended on the inner edge of the toe next to  the great toe.
                     PERONEAL  ARTERY.

  This artery, h, Fig. 207, is smaller than  the anterior tibial,
and situated at the posterior and deep part of the leg ; it de-
scends  upon  the inner side of the fibula,  giving  numerous
branches  to  the peroneal  muscles at *', and the flexor of the
great toe.  At the lower part it divides into the posterior fibu-
lar artery, which, properly  speaking, is the termination of the
peroneal, descending  behind  the  inferior  articulation of the
fibula, at k, to the posterior part  of the foot, and is distributed
to the heel and the ankle 
OF THE  ARTERIES.
421
POSTERIOR TIBIAL ARTERY.
      Fig. 207.
                        This  vessel,  e,  is  the  continued
                      trunk of the popliteal, a;  it descends
                      under the superior attachment of the
                      soleus, between that muscle  and the
                      more deeply  seated flexors  of the
                      toes ; it does not lie, however, in im-
                      mediate contact  with  the  muscular
                      fibres, but  like  the femoral artery  is
                      invested  by  a strong sheath  of con-
                      densed  cellular  membrane.   In  its
                      course the  posterior tibial  artery fur-
                      nishes  a number of small branches,
                      which  are  chiefly  distributed  to the
                      tibialis posticus and the  flexor  mus-
                      cles, the skin, and the periosteum of
                      the  tibia ;  one  of  these  branches,
                      termed  the nutritious  artery of the
                      tibia,  descends  upon  the  posterior
                      surface  of this bone,  and  penetrates
                      into  the medullaryfcanal.   As this ar-
                      tery  descends it  gradually  advances
                      more forwards,  follows the course of
                      the  flexor  tendons, passing  behind
                      the inner ankle, / and upon this bone
                      its pulsation  may be felt;  then sink-
ing under the abductor pollicis, it divides into two branches —
   1st.  The internal plantar artery,  which supplies the mus-
cles situated on  the inner edge  of the sole  of the foot, Fig.
298, b. 
422
VASCULAR SYSTEM.
  2d.  The external plantar artery, a, which crosses obliquely
the three middle metatarsal bones, and forms the plantar arch,

                         Fig. 208.
c, the convexity of which furnishes numerous branches to sup-
ply the lumbricales muscles ;  and taking a  similar course to
the branches of the palmar arch, each anterior branch supplies
the corresponding sides of the  toes, in the same manner as the
collateral arteries are distributed to the fingers.
19 
 


■EBB
■
..... ■ Xt.'*ij
NLM032067648