NATIONAL LIBRARY OF MEDICINE Washington Founded 1836 U. S. Department of Health, Education, and Welfare Public Health Service V A //4 description OF THE ARTERIES OF THE HUMAN BODY. REDUCED TO TABLES. BY ADOLPHUS MURRAY, M. D. /o*r R. and O. Professor of Anatomy and Surgery at Ups^l. TRANSLATED FROM THE ORIGINAL BY ARCHIBALD SCOTT. '*'n * IiISj- - -> ?. ■ PHJfcAMEPHIA: PUBLISHED BY THOMAS DOBSON, At the Stone House, No. 41, South Second street Fry and Kammcrer, Printers. 1810, to Dr. BARCLAY. Dear Sir, Nothing but the desire of complying widi your request, and the confidence I had, as a pupil, in your assistance in every difficulty, could have in- duced me to attempt the following Translation. From the high approbation I have heard you so often express of the original in your Public Lec- tures on Anatomy, I am happy to think that, at a time when literary productions are less easily procured from the Continent, I have it in my power, by the Translation I now present to you, to render these Tables of the Arteries more generally known. I am, Dear Sir, With sincere esteem, Your affectionate Pupil and Friend, ARCHd. SCOTT. Edinburgh, Dec. 1800. THE TRANSLATOR'S PREFACE. \\thile Professor Murray's Description of the Arteries (Published at Upsal in 1798) is not inferior in minuteness and accuracy to those of Haller, Sabatier, and Meyer, it far exceeds them with respect to conciseness, clearness, and arrangement. It is divided into two Sections: the first, comprehending the branches from the Arch; the second, the branches from the Descending Aorta. In both Sections, the First, Second, and Third, and all the succeeding series of arteries, are, when de- scribed, either distinguished by peculiar marks, or printed in a different character. The reader, there- fore, can easily perceive, by a glance of the eye, to what series an artery belongs; and may, if he choose, peruse the description of any particular series of branches independently of the rest. The fulness and accuracy of the description; the decided superiority of arrangement; the facility with which it may be consulted; and the numerous advantages it presents to students of anatomy— were thought, with other motives, sufficient induce- vi THE TRANSLATOR'S PREFACE. ments to undertake the translation. In performing which task, I have constantly endeavoured to render faithfully the meaning of my author, and to do it as clearly as the idioms of the two languages would admit. I have ventured, however, to change the names of a few muscles for those synonymes by which they are better known in this country: and where a muscle was expressed by a single epithet, as profundus mterosseus, I have preferred the Latin to the English name; as the former is not only equally familiar, but, when it is a noun of the second declension, distinguishes also the muscle from the artery by its termination. As Professor Murray, in describing the arteries of the hand, has substituted the terms Radial, Ulnar, Voral, and Dorsal, for the vague and relative terms External, Internal, Anterior, and Posterior, I have extended his mode of expression to the footj and instead of Internal and External Side, have substituted the terms Tibial and Fibular. For this reason, the word Peroneal, when applied to an artery, has been rejected, as being of Greek origin, and as not entering so properly into compounds with the Latin terms. Where he has used sometimes more, and some- times fewer epithets, in describing the artery, I have regularly, where there was no danger of am- biguity, preferred the lesser number, and have THE TRANSLATOR'S PREFACE. vii ventured to convert them into compounds. Thus, I have called a branch of the Humeral Profunda the Profunda Radial, instead of the Larger Communi- cating Radial branch of the Profunda Humeri. I have only to add, that in all those cases where Ulnar, Radial, Tibial, and Fibular, are the last words of a compound, they denote situation or direction; and when the frst, situation or origin. Where any other changes are made, intimation is given in the Notes. My reason for prefixing a Table of Contents in English and Latin, including the names of the prin- cipal arteries, with a reference to the pages where they are described, requires, I hope, no explanation. The utility of this Table will soon be perceived by the young Anatomist. THE AUTHOR'S PREFACE. As the mind of man cannot be more agreeably or more usefully employed, than in the investigation of those arts and sciences, which no less tend to pre- serve and augment our happiness than to obviate the evils to which we are subject; so, in examining the different parts of the human body, anatomists have particularly attended to the properties and courses of the vessels, considering that this study would afford an easy access to the knowledge of the differ- ent functions of the animal economy, and with more certainty enable them to cure those disorders which arise from any lesion of the parts. Accordingly, those who anciently cultivated anatomy, as well as the re- storers of that science, were principally occupied in describing the vessels, and exploring their distribu- tions, directions, and varieties; which laudable in- dustry has been so well supported by later ob- servers, and the doctrine of the vessels so fully treated of in many elegant works, that the subject seems to be exhausted. B x THE AUTHOR'S PREFACE. But as the honour of discovering the circulation is due to the immortal Harvey, so it is chiefly owing to him that anatomists have studied the arteries with such attention, without confining them- selves so particularly as the ancients, to the descrip- tion of the veins. The circulation being discovered, the inquirers into nature soon invented the art of imitating it, by means of a ceraceous preparation, in the dead subject, and thereby of investigating the vessels with more accuracy. They perceived soon, that the distribution of the arteries, even where their ramifications are most minute, are much more re- gular than the veins; and that the branches of these last, being infinitely diversified, seem scarcely to admit of a certain and uniform description. By such discoveries, an ardent and inflexible perseverance being roused in anatomists, they began to scrutinize every part of the human body separately; and not only corrected many ancient errors which had crept into the science, but observed also, in every part, the principal varieties which sometimes take place in the distribution of its arteries; and thus, as might well be expected, obtained a much more accurate knowledge of the structure than could be acquired by those who examined the whole body in a super- ficial and general manner. I forbear mentioning those authors who have de- THE AUTHOR'S PREFACE. xj scribed the arteries, since to those who have been initiated into anatomical studies the most of them are known or recommended. The great defect of these illustrious writers is, that almost all of them have capriciously changed the ancient denomina- tions of the ramifications, and imposed new ones of their own. By this means the young inquirer is led into many errors, and» the study of anatomy itself has been not a little retarded. To remedy these in- conveniences was the design of the illustrious Haller. He, as it were, having made this branch of anatomy his own, explained their distributions more accurately and elegantly than had hitherto been done: nor was this all; but whenever he saw it necessary to substitute new or more apt denomina- tions, he still took notice of the old ones in their proper place. Few, it is to be regretted, make suf- ficient use of this rich treasure of anatomical know- ledge, and examine properly those excellent draw- ings in the work, which are nature itself. Among those, however, who deserve praise for their inquiries into this subject, I cannotforbear men- tioning with approbation Sabatier and Meyer. These anatomists have indeed changed many of the names imposed by Haller; but their writings are remarkably perspicuous, and they have faithfully xii THE AUTHOR'S PREFACE. given the observations of Haller in their com- pends. The figures which accompany the work of Meyer are reduced to a smaller form; but are ac- curate, fair, and extremely useful in dissection. The great scope of this illustrious author seems to have been to furnish a rule to young dissectors; to which, in examining the human body, they might reduce their inquiries, and, at the same time, that they might be able, by his short compend, to commit their observations more easily to memory. It seemed to me, however, more useful to reduce into scia- graphical tables the divisions of the ramifications which proceed from the Aorta; so that any observa- tions concerning a particular branch might more readily strike the eye, and be remembered with greater facility. Having derived great advantage from tables of this kind which I had formed for my private use, I could not help communicating them to my illus- trious colleagues, by whom they were exhibited as exercises; and they are now presented to the public in a more polished and correct form. I have followed everywhere the draughts of the illustrious Haller; which, as well as those observations I was accus- tomed to write down upon dissecting bodies, I have frequently and carefully examined. These have THE AUTHOR'S PREFACE. xiii led me, in some places, to invert the order in which the smaller branches rise from their trunks. I have no- where changed the nomenclature of Haller, since I willingly followed the authority of so great a man. Lest these tables should have too much the appear- ance of a catalogue, I have briefly described the course of every particular branch, if not very ano- malous. I earnestly wish that this essay may be generally useful, and especially to young anatomists, for whom it was principally intended. CONTENTS. THE AORTA, AORTA, PAGE 1 SECTION I. BRANCHES from the ARCH of the AORTA. I. Right Coronary, II. Left Coronary, HI. Right Subclavian, IV. Common Carotid, Common Carotid, External carotid, Superior thyroid, Lingual, Labial, Ascending pharyngeal, Occipital, Posterior auricular, Superficial temporal, Internal maxillary, Internal carotid, Posterior of the receptacle, Anterior of the receptacle, Opthalmic, Communicating, Anterior carotid, Posterior carotid, Two nameless branches. Subclavian, Internal mammary, Inferior thyroid, Superior intercostal, Arteria Coronaria Dextra, ib. Sinistra, 5 Subclavian, - 6 Carotis Communis, ib. Carotis Communis, 7 Arteria carotis externa, ib. thyroidea superior, ib. lingualis, 8 labialis, 9 pharyngea ascendens, 13 occipitalis, 14 auricularis posterior, 15 temporalis superficialis, 17 maxillaris interna, 19 carotis interna, 24 receptaculi posterior, 25 receptaculi anterior, 26 opthalmica, ib. communicans, 31 carotis anterior, 32 carotis posterior, 33 SUBCLAVIA, - - 34 Arteria mammaria interna, 35 thyroidea inferior, 37 intercostalis superior, 41 XVI CONTENTS. page Vertebral, Arteria vertebralis, 42 Deep cervical, cervicalis profunda, 47 Superficial cervical, cervicalis superficiahs, 48 XILLARY, Axillaris, ib. Highest thoracic, Arteria thoracica suprema, 49 Long thoracic, longior, ib. Humeral thoracic, humeraria, 50 Alar thoracic, alaris, 51 Inferior scapular, scapularis inferior, 52 Posterior circumflex, circumflexa posterior, 53 Anterior circumflex. anterior, 54 Humeral, or Brachial, Large profunda, Large nutritious of the") humerus, 5 Lesser profunda, Large anastomotic, Ulnar, Highest interosseal perfo- rant, Ulnar recurrent, Nutritious of the ulna, Common interosseal, Dorsal of the hand, Ulnar profunda, Vola ulnar of the little fin- ger, First vola-digital, Second- vola-digital, Third vola-digital, Large anastomotic, Nameless branches. Humeraria, s. brachialis, 55 Arteria profunda humeri, 56 nutritia magna humeri, 58 profunda minor, - ib. Ramus anastomoticus magnus, 59 Cubitalis, 60 Arteria interossea perforans su- prema, - 61 recurrens cubitalis, ib. nutritia ulnx, 62 interossea communis, ib. dorsalis manus, 65 cubitalis manus profunda, 66 Arteria volaris cubitalis digiti mi- nimi, - 66 digitalis volaris prima, ib. secunda, 67 tertia, ib. Ramus anastomoticus magnus, 68 Radial, Radial recurrent, Superficial volar, Dorso-radial of the thumb, Dorso-ulnar of the thumb, Radialis, Arteria recurrens radialis, ib. 69 superficiahs volx, 71 dorsalis pollicis radialis, 72 ulnaris, ib. CONTENTS. xvn Dorso-carpal, Dorso-radial, Pollicar, or artery of the") thumb, £ Superior volar perforants, Inferior volar perforants, page Arteria dorsalis carpea,- 73 C interossea indicis ma- £ jor, s. radialis, 74 pi'inceps pollicis, - ib. perforantes superiores, 75 inferiores, ib'. SECTION II. BRANCHES from the DESCENDING AORTA, Thoracic aorta, Aorta thorackSa, 77 78 Superior and posteribr pe- Arteria pericardiaca posterior su- ricardiac, perior, - ib. Common bronchial, bronchialis communis, ib. Right bronchial, dextra, ib. Left bronchial, sinistra, 79 Inferior bronchial, bronchialis inferidr, ib. Oesophageal, cesophageae, - ib. Inferior intercostals, intercostales inferiores, 80 Ventral aorta, Phrenic—right and left, Coeliac, Superior coronary, Hepatic, Splenic, Superior mesenteric, Posterior pancreatics, Left inferior duodenals, Superior colic, Ileo-colic, Inferior mesenteric, Left colic, Internal hemorrhoidal, Capsular, or atrabiliary, Renal, or emulgent, Spermatic—right and left, Adipose—right and left, Aorta ventralis, - 81 phrenica, dex. et sinistra, 82 84 COELICA, coronaria superior, hepatica, splenica, ib. 86 90 MESENTERICA SUPERIOR, 91 pancreatics posteriores, 92 duodenales infer, sinist. ib. colica superior, ib. ileo-colica, - - 94 MESENTERICA INFERIOR, 96 colica sinistra, - ib. hxmorrhoidalis internalis, 98 capsulares, s. atrabiliarix, ib. renalis s. emulgens, - 99 Cspermatica—dextra et \ sinistra, - - 100 adiposa—dextra et sinist. 102 XV11I CONTENTS. Ureterics, Lumbar—right and left, Common Iliac, Internal Iliac, Ileo-lumbar, Sacro-laterals, Umbilical, Inferior vesicals, Middle hemorrhoidal, Uterine, Obturator, Posterior iliac, or gluteal, Ischiadic, Common pudic, or pudic,. External Iliac, Epigastric, Circumflex iliac, Common femoral, Superior external pudic, Middle external pudic, Inferior external pudic, Deep Femoral, External circumflex, Internal circumflex, First perforant, Second perforant, Superficial femoral, Large anastomotic, Superior perforant, Inferior perforant, Popliteal, Superior externo-articular, Superior interno-articular, page ureteric*, - - 103 lumbalis—dextra et sinist. ib. Iliaca communis, Arteria iliaca interna, 105 107 Ileo lumbalis, 108 sacra laterales, 109 umbilicalis, - ib. vesicales imz, • 110 haemorrhoidea media, 111 uterina, - 112 obturatoria, - 113 iliaca posterior, s. glutea, 115 ischiadica, - 118 Arteria pudenda communis, 119 Iliaca Externa, • 124 Arteria epigastrica, • 125 circumflexa ileum, &c. 127 Femoralis communis, 129 ■Arteria pudenda exter. superior, 130 externa media, ib. externa inferior, ib. Femoralis profunda, Arteria circumflexa externa, interna, perforans prima, secunda, 131 132 135 138 140 142 Femoralis superficialis, Ramus anastomoticus magnus, 143 perforans superior, 144 inferior, 145 Poplitea, ,. . 146 Arteria articularis super, externa, 147 super, interna, ib. CONTENTS. xix PAGE Middle articular, Arteria articularis media, s. azygos, 148 Inferior externo-articular, infer, externa, 149 Inferior interno-articular, infer, interna, ib- Anterior tibial, Tibial recurrent, Internal malleolar, External malleolar, Transverse tarsal, or tarsal, Transverse metatarsal, Dorso-metatarsal, Deep anastomotic, Tibialis antica, - 151 Arteria tibialis recurrens, 152 malleolaris interna, - 153 externa, ib. Arteria tarsea, - - 154 metatarsea, 156 dorsalis externa halucis, 157 Ramus anastomoticus profundus, 157 The Posterior tibial, Posterior interosseal, Common fibular, External plantar, Internal plantar, Tibialis postica, Arteria interossea posterior, peronea communis, plantaris externa, interna, 158 159 ib. 164 169 I A DESCRIPTION OF THE ARTERIES OF THE HUMAN BODY; REDUCED TO TABLES. THE AORTA. The large artery, termed aorta, opens with a wide orifice in the superior and posterior side of the left ventricle of the heart. Its roots seem in- corporated with the substance of the heart itself; as it is not only closely united with its internal surface, but some muscular stria; of the ventricle are also mixed with the white line, which is called 2 THE AORTA. Tendo Arteriosus, and which defines the extent of the muscle. Some transverse fibres of the heart are united to the aorta from without, and cover it for a line and an half, though a little more loosely at the extremity. The aorta having left the heart, is immediately expanded; nor does it again recover its first diameter till it reaches the place where it sends off the subclavian artery of the right side. In its ascent, it is first inflected to the right, behind and beyond the pulmonary artery; it then gradually inclines itself to the left, till, having formed a transverse arch, it is seen projecting be- hind the lungs, at the left side of the vertebrae. From these it receives its chief support, and de- scends along with them in the same straight line; till at last, having entered the abdomen, it again begins to turn towards the right, or rests upon the middle of the vertebrae. By the arch of the aorta, is understood that part of it which is bent nearly in the form of a parabola, and which maintains the curved direction already mentioned, though its right pillar at first stretches to the right, and then proceeds to the left, while the left advances almost in a straight line. I exclude the ancient and now absolete distinction of the aorta into the ascending, transverse, and descending. When we consider the whole extent of the arch, we observe that it leaves the ventricle at the THE AORTA. 3 inferior margin of the third rib, and rises in an oblique and winding course to the lower margin of the first rib; and that its diameter must be so re- ferred to the external parts, as that its exterior and right extremity shall correspond to the middle of the cartilages of the ribs; and its left extremity, concealed by the left lobe of the lungs, and pro- ceeding onwards, shall, in like manner, correspond to the vertebral extremity of the ribs. SECTION I. BRANCHES FROM THE ARCH OF THE AORTA. I. The two Coronary Arteries of tite Heart, viz. the Right Inferior and Left Superior. These being sent off above the interior and poste- rior semilunar valves, form, in returning to the heart, an acute angle with the rising trunk. II. The Right Subclavian or Innomi- nata. III. The Left Common Carotid. IV. The Left Subclavian. The three last arise as distinct branches from the superior convexity of the arch. The first of them passes obliquely over the Trachea or Wind- pipe, upwards, and to the right; and after advanc- ing about two inches, divides at its right extremity into the right common carotid, and the right subclavian, which passes under the Clavicle to the arm. The other two branch out from the Aorta near to the former, and are also similar to them. I. The Right Coronary—is larger than the Left. Being covered with fat, it runs between Sect. I. ARCH OF THE AORTA. 5 the auricle and ventricle to the flat surface and apex of the heart, inosculating freely with the left coronary, both by its branches and the extremity of its trunk. These branches are, a. One running on the right to the aorta, and on the left to the pulmonary artery. b. A number going to both sides of the right au- ricle—to the two venae cavae—to the sinus be- hind—to the aorta—and to the pulmonary veins. c. Five branches winding on the convex surface of the heart; the longest of which unites with the left coronary branches beyond the septum, near the apex. d. Branches passing over the plain surface and right ventricle, as far as the apex of the heart. II. The Left Coronary—after going out be- tween the pulmonary artery and the left auricle, divides into two branches— a. An anterior Branch, running upon the convex surface of the heart, towards the septum, in a winding direction, to the apex, where it is reflected on the posterior surface of the heart. This gives, 1. Branches, to the trunks of the arteries, uniting with those of the right coronary. 2. Numerous branches to the left ventricle. b. A Circumflex Posterior Branch, which, wind- ing between the left sinus and the ventricle to D 6 BRANCHES FROM THE Sect.1. the rounded extremity of the heart, terminates towards the apex, upon the flat surface. It gives * Branches, running upwards, and extensively * ramified on the left sinus and the left auricle, and proceeding at last to the inferior vena cava. * * Branches, losing themselves in the muscle of the left side of the heart. JV. B. A third branch is sometimes found sunk deep in the septum. The coronary arteries run in innumerable twigs to each muscular fasci- culus of the heart; and wherever they ap- proach the branches of the phrenic, internal mammary, and bronchial arteries, they com- municate with them by frequent inosculations. III. The Right Subclavian.—For the de- scription of this and the Left one, see below. IV. The Common Carotid-—has on each side a similar distribution of its branches, though the Right be a little larger than the Left. It lies on the anterior surface of the vertebrae, and is united by cellular membrane to the intercostal nerve—the par vagum beneath, and the internal jugular vein above. It thus ascends in one continued trunk in a straight direction, and parallel to the Trachea, as high as the superior margin of the thyroid cartilage. It there divides into branches of equal size; the anterior of which is called the external carotid; and the posterior, the internal or cerebral. Sect. I. ARCH OF THE AORTA. i DISTRIBUTION OF THE COMMON CAROTID. (I.) The External or Superficial Caro- tid. This artery has scarcely arisen, when it ad- vances forwards, and divides into eight branches, variously distributed. A. The superior thyroid, issuing near the ori- gin of the trunk, and descending in a winding course to the superior margin of the thyroid gland, gives out, a. The Superficial Ascending Branch, running above or below the os hyoides, and there forming an arch with the branch from the op- posite side. This again divides into, «. Branches going to the hyo-thyroideus, sternq and omo hyoidei muscles, the platysma myoi- deus, and skin. /3. Branches to the ligament, which unites the thyroid cartilage to the os hyoides. b. The Superficial Descending Branch, running downwards, and dividing into several branches, with various communications. These are distri- buted to, 1. The sterno mastoid, platysma myoideus, the thyroid cartilage, the hyo and crico thyroidei muscles, and the middle and lowest constrictor muscles of the pharynx. Some of these occa- sionally come off from the superior ascending branch. 2. A branch, uniting with the same artery, from the opposite side, above the cricothyroideus, and there forming a ring. c. The Laryngeal Branch.—Larger, and often pro- ceeding from the superficial ascending branch. BRANCHES FROM THE Sect. I. It hides itself, with its attending nerve, be- tween the cricoid and the thyroid cartilages; or penetrates the membranous interstice be- tween the thyroid cartilage and the os hyoides; or even sometimes runs to the interior part of the larynx, through a passage peculiar to itself in the thyroid cartilage, and at last sends off, a. An ascending branch—going to the upper margin of the epiglottis and its membranes. (i. A transverse branch—given to the posterior arytenoid and cricoary tenoid muscles. y. A descending branch—running to the thyro- arytenoid—the lateral and posterior cricoaryte- noid—the lateral ligament—and the ligamen- tous expansion spreading outwards. A small trunk at last goes out, and loses itself in the cricothyroideus. d. The Thyroid Branch—inosculating in the sub- stance of the gland itself with the thyroid branch of the inferior thyroid artery,and also by various twigs with the branch from the opposite side. B. The lingual, or sublingual artery, wind- ing above the os hyoides, forwards, upwards, and inwards, to the tongue. At its com- mencement, it either passes over, or is covered by the hyoglossus; then is concealed by the genioglossus. At the anterior margin of the hyoglossus, it is subdivided into e and £. It gives off, a. Branches to the middle constrictors of the pharynx. s. The Hyoidal Branch—often uniting at the su- perior, but sometimes the inferior, margin of Sect. I. ARCH OF THE AORTA. 9 the os hyoides, with the opposite branch, and distributing twigs to the contiguous mus- cles of the os hyoides and tongue. y. Branches penetrating the fibres of the hyoglos- sus or its interstices, if the trunk be conceal- ed; proceeding to the mylohyoideus, genio sterno, and coraco-hyoidei, and the digastric. 3. The Dorsal of the Tongue—running outwards and upwards, near the insertion of the stylo- glossus. Having reached the dorsum of the tongue and the epiglottis, it forms a plexus with the branch of the opposite side, and is ramified upon the adjoining part of the pharynx. i. The Sublingual—the superficial branch of the divided trunk, rising to the symphysis, be- tween the sublingual glands and the genio- hyoideus, often penetrating the mylohyoideus, and losing itself in the integuments of the chin. If larger, it often supplies the place of the submental artery. In this course it sends off many irregularly disposed branches; of which the most remarkable are, 1. Branches to the sublingual gland. 2. Branches to the geniohyoideus, mylohyoideusj the digastric, and skin. 3. Branches to the inferior lip. £. Ranina—a larger branch, going off at an ob- tuse angle from the trunk. It runs tortuously between the fibres of the genioglossus to the surface and point of the tongue, passing along the middle, on the inferior side. C. The LABIAL, EXTERNAL MAXILLARY, ANGU- LAR, or facial—Concealed by the stylohy- BRANCHES FROM THE Sect. I. oideus, and the tendon of the digastric. As- cends, in a tortuous manner, forwards, through the depression for the maxillary gland, and, winding above the maxilla, follows the an- terior margin of the masseter;—afterwards branches out, under the zygomatic muscles, in serpentine windings, upon the face and the sides of the mouth and nose. The numerous branches proceeding from this artery are di- vided into two classes: The first, compre- hending those arteries that leave the trunk be- fore it reaches the maxilla, from 1 to 6; the second, the branches distributed on the face itself, from 7 to 12. 1. The Ascending Palatine—covered by the styloid muscles—lies upon the sides of the pharynx, near the external margin of the in- ternal pterygoid muscle. Twigs being sent from it to these muscles, to the tongue, the tonsils, and the Eustachian tube, it is divided, near the sides of the levator palati, into * A Superficial Palatine Branch—following the course of the circumflex muscle of the palate^ and distributing twigs to the pendulous velum and its glands. • * A Deep Palatine Branch—perforating the velum under the levator palati, and copiously supplying with branches the uvula, palate bone, tonsils, and tendinous expansion of the circumflex. 2. Minuter branches to the stylohyoideus, the stylopharyngeus, the hyoglossus, and glands. >. The Tonsillar Branch—sometimes wanting— near the insertion of the styloglossus pene- Sect. I. ARCH OF THE AORTA. H trates the lateral parts of the pharynx to the tonsils, and exhausts itself in numerous small branches, spreading on their surface, and reaching to the tongue. 4. A cluster of twigs, regularly sent off from the trunk in the furrow or depression already mentioned, and beautifully subdivided on the maxillary glands. Some of them run to the pterygoideus, the tongue, the integuments of the neck, the chin itself, and even to the mas- seter. 5. The Pterygoid Branch—often double—dis- tributed to the internal pterygoid, the mylo- hyoideus, the superior constrictors, the con- strictors of the isthmus of the fauces, and sometimes to the tongue. 6. The Submental Branch—goes out near the bend of the trunk, above the maxilla, between the anterior part of the digastric, the mylo- hyoideus, and the margin of the maxilla, al- most to the symphysis of the chin, where it divides into fi and y. When it supplies the place of the sublingual, it distributes a great abundance of twigs; and commonly st. A number of branches, variously ramified on the maxillary glands, the skin, the mylohyoi- deus, and the mouth. 0. A superficial Branch—ramified on the qua- dratus, or depressor of the inferior lip, and the skin. y. A Deep Branch—covered by the quadratus; distributed to the levator menti, the triangu- laris, or depressor of the angle of the mouth, the orbicularis, and skin, and inosculating with the branches of the inferior labial. BRANCHES FROM THE Sect. I. 7. The Masseteric Branch—United with abranch of the temporal artery of the same name upon the surface of this muscle. 3. The Inferior Labial, or Superficial Branch— rises, often double, from the trunk, goes for- wards, and, having sent branches to the buc- cinator, the depressors of the angle of the mouth and lips, and the orbicular, distributes others, uniting with the inferior labial of the opposite side, with the inferior coronary, and the inferior maxillary; and then passes under the depressor of the angle of the mouth to the inferior lip, dividing into two, and sometimes producing the inferior coronary of the lip. 9. Many branches, spreading outwards above the buccinator, and interwoven with the transverse of the face, the buccal, and the alveolar. 10. The Coronary of the Inferior Lip—goes off near the angle of the mouth, and, covered by the depressor of the angle and the orbicular, proceeds towards the cavity of the mouth, in a winding and transverse direction, under the membrane of the mouth, to its fellow of the opposite side, with which it inosculates. From this are distributed, 1. Branches to the masseter, the parotid gland, Steno's duct, the buccinator, and the orbicular. 2. Branches descending to the quadratus and skin, and inosculating with the neighbouring arteries. 11, The Coronary of the Superior Lip—like the preceding, but larger and more tortuous, passes under the greater zygomatic and the orbicular muscles, runs along the margin of the superior lip, and gives Sect. I. ARCH OF THE AORTA. 13 1. Branches to the orbicular muscle and levators of the superior lip. 2. The Lateral Nasal Branch—uniting with the naso opthalmic, and forming a beautiful vascu- lar plexus upon the alse of the nose. 3. The two Nasal Branches of the Septum—rising upwards from the middle of the lip, and run- ning as far as the point of the nose. 12. Two or three branches, uniting, under the levator labii superioris proprius, with the in- fraorbital, and other smaller branches perforat- ing this levator muscle, and uniting also with the palpebral arteries. D. The ascending pharyngeal artery of Haller—issues near the lingual, or from the bifurcation of the carotid, but more posteriorly from the trunk. The auricular excepted, it is the smallest of the branches. It is united by the tela cellulosa to the long anterior rectus muscle, and rises anteriorly towards the foramen lace- rum, through which it passes to be lost in the dura mater. The branches which go off in its ascent may be divided, in regard to their situation, 1. Into those passing Inwards, viz. a. An Inferior Pharyngeal Branch—stretching down, and supplying the lower part of the mus- cular sac. b. A Middle Pharyngeal Branch—distributing many twigs in the region of the larynx, pharynx, and Eustachian tube, after having united itself with the superior thyroid artery. c. A Higher Pharyngeal or Palatine Branch—dis- tributing some twigs to the superior constric- 14 BRANCHES FROM THE Sect. I. tors, the stylopharyngeus, the Eustachian tube, and the pendulous velum; others to the rectus minor, the cuneiform bone, the cartilage oc- cupying the anterior part of the foramen lace- rum—and others to the internal parts of the nostrils, and the pterygoid canal. 2. Those passing Outwards.—Of which the most remarkable are, a. Branches to the first intercostal ganglion and the par vagum. (S. Branches to the sternomastoid and the con- globate glands of the neck. y. A branch passing through the opening with the jugular vein, and extending its minute twigs even to the cavernous sinus. E. The occipital artery—passes transversely before the jugular vein, above the rectus la- teralis, proceeding between the transverse pro- cess of the atlas and the mastoid process, to the back part of the neck, and rises, in many wandering branches, to the occiput. In its course it is covered by the digastric, the trachelomas- toid, the splenius, and complexus; and becomes subcutaneous as it reaches the occiput. Its branches are, a. One to the digastric and stylohyoideus. b. Branches to the glands of the neck and the sternomastoid, inosculating with the ascend- ing thyroid artery. r. A Meningeal Branch—which enters the cra- nium along with the jugular vein, and is dis- tributed to the surface of the dura mater of the cerebellum. d. An Auricular Branch—distributed to the lesser Sect. I. ARCH OF THE AORTA. 15 lobe and the helix, and sometimes behind on the concha. e. Branches to the splenius and trachelomastoid. Of these, the descending branches go to the lateral and oblique recti muscles. f. A Large Cervical Branch—passing to the ex- terior margin of the complexus, and going down between this and the trachelomastoid. -J- A Superficial Branch—descending often to the middle of the neck; and, giving twigs to the splenius, complexus, and skin, at last inoscu- lates with the transverse thyroid artery of the neck. -f- -f- A Deep Branch—distributed to the obliqui recti and complexus, and uniting with the ver- tebral artery under the transverse process of the atlas. §\The artery, having now bent towards the vertex of the head, branches go off in a retrograde course to the splenius and complexus; whilst other branches are so extensively ramified, that a great number of them inosculate with the higher twigs of the temporal artery. Of these, one perforates the occipital ridge, and another the posterior mastoid hole—both of them going to the dura mater. F. The posterior auricular, or styloma- stoid.—This artery rises from the trunk in the parotid gland, above the digastric muscle, and before the styloid process, and passes trans- versely to the ear. As it ascends in a curved direction behind the ear, it inclines to the posterior part of the squamous bone, inos- culating, first with the temporal, and then 16 BRANCHES FROM THE Sect. I. with the occipital arteries. It divides into, a„ Numerous branches, going to the parotid gland, the digastric and sternomastoid muscles. b. A branch, passing through a particular open- ing in the meatus auditorius of infants, is distri- buted to its membrane. c. The Stylomastoid Branch—passing outward to the stylomastoid hole, where it enters, artd ex- hibits the following branches: 1. An external one to the cartilaginous part of the meatus. 2. The First Branch of the Tympanic Artery.— This, in passing along with a twig of the arti- cular artery of the maxilla, sends out the coro- nary branch, which surrounds the osseous part of the meatus auditorius, and, descending to the membrane of the tympanum, shoots out into the most beautiful ramifications. 3. Branches to the mastoid cells, the muscle of the stapes, the external semicircular canal, and the nerve. 4. A branch, anastomosing at the superior and posterior part of the tympanum with the menin- geal branch, passing through the aqueduct of Fallopius to the cavity of the ear. d. Minute branches to the sternomastoid muscle, the skin, and vertex of the head. e. Branches behind the ear to the posterior auri- cular, the occipital and splenius muscles, and distributed more deeply to the mammillary process, the pericranium, and the occipital bone. /. A branch, winding on the posterior part of the concha of the5 ear, and sending twigs to the cartilage, to inosculate with the ramuli of the anterior auricular artery. Sect. I. ARCH OF THE AORTA. 17 g. Higher branches, spreading under and above the aponeurosis of the temporal muscle, and inosculating before with the temporal, and be- hind with the occipital branches. G. The superficial temporal.—This artery, concealed at first in the parotid gland, rises in a straight line above the zygomatic arch, between the maxilla and meatus auditorius, and is at last extensively ramified on the aponeurosis of the temples and the neighbouring parts. In this course are sent off, 1. A number of branches to the parotid gland, equally irregular in size and number. 2. The Articular Artery of the Maxilla—running to the posterior part of the meatus auditorius; spending branches to the articular cartilage, and transmitting two twigs along the portio dura, through the fissure of the articulation, where they reach the muscle of the malleus, and, in- osculating with the stylomastoid, form the other half of the coronary artery of the tym- panum. 3. Two or three masseteric branches, going to the masseter muscle, and afterwards inosculating with the branches of the coronary artery of the inferior lip and the buccalis, or artery of the cheek. 4. The Transverse Artery of the Face—rising under the zygoma from the parotid gland, it proceeds transversely to the face along with the salivary duct. In this course, if double, it gives branches to the parotid gland, the arti- culation of the maxilla, the masseter, the skin, the zygomaticus, and the orbicularis palpe- brarum. It inosculates with the alveolar, pal- 18 BRANCHES FROM THE Sect. 1 pebral, infraorbital, and coronary arteries of the upper lip; and sometimes gives rise to masseteric branches. 5. The Middle or Deep. Temporal Branch— sent off below the zygoma. This Branch passes over the zygomatic arch, and is im- mediately covered by the aponeurosis of the muscle, where it extends to the anterior part of the temporal muscle, to the external angle of the orbit, and inosculates with the palpebral artery. 6. The Anterior Auricular Arteries—rising above the origin of the middle temporal. Some of these perforate the meatus auditorius, and form a retiform plexus with the posterior auricular artery; others go to the helix and antihelix, the anterior auricular muscle, and meatus auditorius. 7. The Orbicular Branch—rising often from the temporo-frontal artery, passing above the zygo- matic arch, sends a small branch, in a tortuous direction, to the external can thus of the eye, which, running under the orbicularis, reaches the internal angle of the orbit. In this course, it inosculates with the palpebral and frontal branches, and, with the frontal, forms the superciliary arch. 8. The Temfioro frontal, or Internal Anterior Branch—distributed extensively towards the forehead, and sometimes reaching as far as the glabella. It sends branches, which rise almost at right angles from the trunk, to the orbicu- lar, corrugator, frontal muscles, and aponeu- rosis. 9. The Temfioro-occipital, or External Posterior Sect. I. ARCH OF THE AORTA. 19 Branch—bending towards the ear, backwards and behind it, forming, as it were, a continua- tion of the trunk—is distributed, in numerous ramifications, to the occipital and lateral parts of the head; inosculates with the occipital about the lambdoidal suture, with the temporo- frontal before, and above with the branches stretching from the opposite side. A". B. The Temporal Artery gives many minute branches to the pericranium, and the bone. H. Internal maxillary.—This artery is lar- ger than the temporal: It rises above the la- teral ligament of the maxilla, about the middle of the ramus of the inferior maxillary bone, before the external pterygoid; and, bending in- wards, forwards, and downwards, is concealed under the maxilla. It then rises obliquely up- wards and forwards, to the space lying between the tuber maxillare and the pterygoid process; and as it proceeds in a tortuous manner, it is lost here in three or four branches, or rather in the spheno-maxillary fissure. In this course it gives 1. The Deep Auricular Artery—going to the posterior part of the meatus auditorius, and giving twigs to this and the neighbouring glands. It is sometimes wanting. 2. The Artery of the Tympanum—which, having sent ramuli to the fat of the maxillary articu- lation, passes through the fissure of Glasserus to the anterior muscle of the malleus. 3. The Small Meningeal Artery—running to- wards the basis of the skull, parallel to the 20 BRANCHES FROM THE Sect. I. middle meningeal. It gives in its course branches to the external pterygoid, to the palatine muscles, and to the third branch of the fifth pair of nerves. It then passes through the foramen ovale, to the membranes of the receptacle, between the pterygoid process and the circumflex muscle. 4. The Middle Meningeal Artery—passing in a straight direction to the foramen spinosum, where it enters this hole; and is there so rami- fied upon the surface of the dura mater, that some branches are carried transversely under the temporal bone to the occipital, others to the posterior sinus of the falx, while others bend a little more anteriorly. All of these have frequent anastomosings with one another, as also with the posterior meningeal branches rising from the vertebral and occipital arteries, and with the anterior branches from the opthalmic. Before reaching the foramen spinosum, it sometimes gives branches to the sphenoid bone, and through that bone to the dura mater, and others to the external ptery- goid, and the muscles of the Eustachian tube. Having passed the foramen spinosum, it sends ■j- Three or four branches to the junction between the petrous and squamous portions of the tem- poral bone. ~j_ _j_ Two branches passing through the aque- duct of Fallopius; one of them following the course of that canal, the other going to the in- ternal muscle of the malleus, and the cavity of the tympanum. -f- + + Branches, which sometimes pass through Sect. I. ARCH OF THE AORTA. 21 hole of the large wing of the sphenoid bone, going to the os malae and the lachrymal gland. The meningeal artery sometimes sends off the la- chrymal artery within the cranium. 5. The Inferior Maxillary Artery—going down, in company with the nerve of the same name, to the inframaxillary canal. As it enters the canal along with the nerve, it sends branches to the internal pterygoid and the mylohyoide- us; and is so distributed on the canal of the bone, that some posterior branches go to the dentes molares and the bone itself, while an- terior twigs enter the alveolar process of the incisores: Then passing through the infra- maxillary hole, it inosculates with the labial branches, and is distributed to the adjacent muscles and lip. 6. Pterygoid Branches—varying in number—.and distributed, both superficially and more deeply, on the pteiygoid and buccinator muscles. 7. The Deep External Temporal Artery—before the trunk is concealed by the zygoma, gives a branch, which, in its ascent, rests upon the tendon of the temporal muscle, and terminates in this muscle and adjoining parts; while an- other, which some call the masseteric, is sent outwards and forwards between the processes of the maxilla, to the external pterygoid and masseter muscles. 8. The Deep Internal Temporal Artery—rising in that part where the trunk proceedstransversely near the antrum Highmorianum, terminating in the temporal muscle, and transmitting a F 22 BRANCHES FROM THE Sect. I. twig through the cheek-bone, to supply the fat and periosteum of the orbit. 9. The Buccal, or Artery of the Cheek—irregular in its origin, arising, sometimes from the ex- ternal deep temporal artery, sometimes from the alveolar, and sometimes from the infraor- bital—penetrates the buccinator; and, winding on its surface, gives branches to the zygomati- cus, the levator, the glands, and the adipose substance. 10. The Alveolar Artery—proceeding in a tor- tuous direction, above the alveolar processes and the superior maxillary bone, towards the cheek and face—where it gives, a. Branches to the buccinator, fat, and internal surface of the cheek bone, and the gums. b. Branches entering, by minute holes, the antrum ■ Highmorianum. c. The Superior Maxillary Artery of the Teeth— passing through the perforation in the tuber maxillare; and as it runs along the canal of the bone, giving branches, with some from the in- fraorbital, to the dentes molares, canini and in- cisivi. 11. The Infraorbital Artery—rising in the sphe- nomaxillary fissure, near the infraorbital groove; and, passing along this canal, emerges at last upon the face through the infraorbital hole. Before the trunk reaches the canal, branches are distributed to the fat and dura mater of the orbit, to the lachrymal gland, and to the inferior oblique muscle of the eye. From the canal, -f- Branches go to the orbicular muscle, the la- chrymal sac, and the nose. Sect. L ARCH OF THE AORTA. 23 -J—J- Branches, through the bone, to the antrum Highmorianum, or maxillary sinus, and its membrane. Beyond the canal, and upon the face, «. Branches anastomosing with the nasal, labial, the transverse of the face, and buccal arteries. (h. Branches to the buccinator muscle, the levator anguli oris, and the levator labii superioris. 12. The Superior Palatine, Descending, or Ptery- gopalatine Artery—rising, often double, from the trunk, that is divided into three branches at the sphenomaxillary fissure. It enters the pterygopalatine canal; and there, if not sooner, divides into two branches; a. A Posterior Branch—turning backwards through the posterior palatine hole, going to the extremity of the palatine bone and the velum palati, and communicating with the ascending palatine branch. b. An Anterior Branch—larger than the last, pas- sing forward under the roof of the mouth, and forming a vascular plexus in the palate. A single twig ascends through the foramen incisivum to the inner side of the nose, or inosculates with the nasal branch as it passes down. 13. The Highest Pharyngeal Branch—rising in he place already mentioned; stretching be- hind the sphenoidal sinuses, to the upper, posterior, and lateral parts of the pharynx— where it gives v.. Nutritious branches, entering their several aper- tures in the sphenoid bone and the pterygoid processes. /S. A Branch, going to the pterygoid hole, and in- osculating with a branch, rising either from the internal carotid, the pharyngeal, or the middle meningeal arteries. 24 BRANCHES FROM THE Sect. 1. y. A branch to the cartilage of the Eustachian tube. I have sometimes found this pharyngeal branch entirely wanting. 14. The JVasal Artery—the last branch of the trunk, and often double, passing through the spheno-palatine hole, and dividing, at the su- perior and posterior part of the nose, into a. A small branch, going to the posterior ethmoid cells. b. Branches to the sphenoidal sinuses. c. Larger branches to the septum of the nose. d. A large branch, passing through the superior and inferior spongy bones to the bottom of the nose; giving twigs to the antrum and the mem- branes of the nostrils, and inosculating with the anterior palatine branch as it passes through the foramen incisivum. (II.) The Internal Carotid, or Cerebral Artery.—This artery, as it rises to its canal, is connected before, by means of cellular substance, to the par vagum and intercostal nerves; and be- hind, to the rectus anticus muscle. Sometimes it forms above the vertebrae a larger or a smaller pro- jecting curvature. In this course no branches are, in general, given off. At last it enters the foramen caroticum; and-, passing along this canal, undergoes many remarkable inflections. On its first entering the foramen, where it forms an obtuse angle, the artery proceeds upwards, inwards, and a little for- wards. As it begins to rise from the canal forwards and upwards, the second curvature appears very obtuse. Having at last reached the posterior part Sect. I. ARCH OF THE AORTA. 25 of the sella turcica, it is so inflected in the caver- nous sinus or receptacle, as to run in a horizontal direction to the anterior clinoid process. It here rises perpendicularly, perforates the internal surface of the dura mater, and proceeds, near the bottom of the brain, backwards to the cerebrum. Thrqugh this tortuous course, the five following branches are chiefly remarkable: A. One to the pterygoid canal, inosculating with a branch of the highest pharyngeal from the internal maxillary. B. A branch, spreading out in the canal itself, going to the cavity and promontory of the tympanum, and anastomosing with a branch of the meningeal, passing under the fissure of the aqueduct. C. The posterior artery of the receptacle or cavernous sinus—rising from the trans- verse part of the carotid concealed in the re- ceptacle, and going to that part of the dura mater which covers the posterior clinoid pro- cesses and the cuneiform occipital process; in- osculating with branches of the vetebral artery rising without the cranium, and entering it through the foramen magnum. a. Many branches, distributed extensively on the dura mater. b. Branches to the 4th, 5th, and 6th, pairs of nerves. c. Branches to the pituitary gland, its periosteum, and the cuneiform bone. 26 BRANCHES FROM THE Sect. I. D. The anterior artery of the receptacle— rising above the root of the intercostal nerve. Some anatomists, from supposing the intercostal to have its origin from the first branch of the fifth pair, have mistaken this artery for a nerve. a. Branches to the 3d, 4th, and the three divi- sions of the 5th pair, with which they go out. /3. Many branches to the dura mater of the re- ceptacle, near the sphenoidal fissure, and some to the pituitary gland. E. The opthalmic artery—rising in the angle where the carotid artery leaves the sphenoid bone, near its anterior clinoid processes, and running with the nerve which accompanies, and rests upon it, through the optic hole, to the orbit of the eye. In mentioning its branches, and their subdivisions, I shall observe the order which Nature generally points out in sending them from the trunk. After lying by the ex- ternal side of the optic nerve, it passes obliquely forwards over the nerve; and reaching the in- ternal angle of the eye above its adductor mus- cle, divides into two branches; and these again into the following smaller branches: l.The Lachrymal—rising from the opthalmic ar- tery, about two lines after it enters the orbit, between the abductor and the levator; and then running above the abductor, proceeds to the lachrymal gland. It sometimes goes off from the middle meningeal artery. a. A recurrent branch to the receptacle and the dura mater, giving twigs to the fifth pair of nerves. Sect. I. ARCH OF THE AORTA. 27 b. Branches to the periosteum of the orbit c. A branch to the levator palpebrae and the optic nerve. d. A branch to the abductor muscle. e. A branch perforating the zygoma, and inoscu- lating with the internal deep temporal artery. f. Many branches, expended on the lachrymal gland. g. The Inferior External Tarseal Branch—form- ing the tarseal arch at the margin of the lower eye-lid, with the inferior palpebral branch. h. The Superior External Tarseal Branch—form- ing a similar arch with the superior palpebral branch. 2. The Long Ciliary Branch.—A description of the Ciliary arteries will be given below. 3. The Supraorbital or Superior Muscular Branch —rises, while the trunk crosses the nerve, un- der the periosteum of the orbit; then bending to the levator palpebrae, proceeds forwards, and, after passing through the supraorbitary hole, is distributed, upon the forehead, in two separate branches. a. Branches going to the superior oblique, the levator palpebrae, the superior recti muscles, the sclerotic coat, and the periosteum. b. An Inferior Branch—widely distributed on the periosteum of the os frontis, and inosculating with the temporal and frontal branches. c. An External Branch—covered by the orbicular muscle, to which it gives twigs, as also to the corrugator. It forms many anastomoses with the neighbouring branches. 4. The Central Artery of the Retina—rising from the inferior side of the opthalmic trunk as it lies upon the optic nerve; or sometimes from 28 BRANCHES FROM THE Sect. I. the ciliary arteries. It then sinks into the nerve; runs along its axis; penetrates, often double, the medullary expansion of the retina; and, branching into many new divisions, is exten- sively ramified on its internal surface. Of these, some extending as far as the corpus ciliare, form a circle between it and the vitre- ous humour, giving twigs to the crystalline lens; while a particular branch passes through the centre of the vitreous humour to the pos- terior side of the lens. 5. The Long Internal Ciliary Artery. 6. The Inferior Muscular Artery—rising from the trunk at the interior margin of the optic nerve, very often between the ciliary arteries, and transmitted, either under the eye, or above the adductor muscle, to the inferior palpebra. a. Many branches to the deprimens oculi, adduc- tor, optic nerve, and sclerotic coat. b. Branches to the inferior oblique. c. Branches inosculating with the infraorbital, and winding on the periosteum of the orbit. d- Branches running to the inferior eye-lid, the tunica adnata, and sometimes reaching the lachrymal sac. 7. The Inferior Ciliary Artery.—This is want- ing sometimes. The three ciliary arteries mentioned above, com- monly arise from the opthalmic artery, in such a way, that the external follows the external margin of the nerve; the internal, the inner margin; while the inferior, with similar wind- ings, runs near the inferior muscular, along the lower margin of the nerve. There are some- Sect. I. ARCH OF THE AORTA. 29 times six ciliary arteries, which, whether they arise from the opthalmic or its branches, spread jnto several ramifications, and enter the sclerotic in such a manner as naturally to fall under three classes. 1. Short, or Posterior Ciliary Branches—aris- ing from the superior and inferior muscular branches, and from the ethmoidal. They are often thirty in number; perforating the sclerotic coat, near the optic nerve, while they pass to the choroid coat, behind. 2. Long Ciliary Branches—Two in number, en- tering obliquely the posterior part of the sclero- tic, dividing into two branches as they ap- proach the ciliary circle, and inosculating round the greater circle of the iris. 3. Anterior Ciliary Branches—rising either from the muscular, opthalmic itself, or the palpebral. They accompany the recti muscles; and, be- ing divided at a little distance from the cornea into three or four branches, enter the sclero- tic, and are distributed among the long ciliary branches on the uvea. To all these, forming a singular vascular plexus, the choroid coat, the ciliary circle with its processes, and the iris, owe their origin. 8. The Posterior Ethmoidal Arteiy—running be- tween the levator and adductor muscles, above the greater oblique; enters the posterior orbi- tary hole; passes through the cribriform plate into the cranium; and, reaching near the dura mater, inosculates with the anterior ethmoidal branches. The rest of the trunk is distributed to the nose. «. A branch to the superior oblique and the ad- ductor. G 30 BRANCHES FROM THE Sect. I. 0. A branch to the posterior cells of the ethmoid and sphenoid bones, where it inosculates with branches of the internal maxillary nasal branch. 9. The Anterior Ethmoidal Artery—rises where the trunk, as it passes over the fourth pair of nerves, reaches the trochlea. It then enters the anterior orbitary hole, and proceeds into the cranium through a peculiar opening near the ethmoid cells, distributing some ramuli, to the nose. a. Branches to the frontal sinuses, to the anterior ethmoidal and nasal sinuses, inosculating freely with the nasal branches. b. Branches, distributed to the dura mater and the fAx. 10. The Inferior Palpebral Artery—rising often along with the superior palpebral, at that place where the trunk generally leaves the tendon of the superior oblique. a. A branch to the tarseal ligament, angle of the eye-lids, the caruncula lachrymalis, and the tunica adnata. fi. Branches to the anterior ethmoid cells, inoscu- lating with the anterior ethmoidal, and passing with the infraorbital branch to the lachrymal sac. y. Branches running along the margin of the tar- sus, forming with the lachrymal the tarseal artery, or inferior tarseal arch. II. The Superior Palpebral Artery___ 1. Branches going to the superior part of the orbicular muscle, to the ligament of the palpe- brae, and to the caruncula lachrymalis. 2. A branch, forming with the lachrymal artery, near the tarseal cartilage, the superior tarseal arch. 12. The JVasal Artery-rising over the superior Sect. I. ARCH OF THE AORTA. 31 part of the lachrymal sac and the ligament of the eye-lids, goes to the nose. a. A branch to the glabella and the frontal mus- cles; from which a twig runs transversely. b. A branch, passing down beyond the tarseal liga- ment to the lachrymal sac, and then to the or- bicular, where it inosculates with the infraor- bital branch. c. A branch, running down on the side of the nose, Where it forms a beautiful plexus, by frequent communications with the labial arteries. Having passed through the bone and nasal cartilage, it is lost on the Schneiderian or pituitary membrane. 13. The Frontal Artery—at first subcutaneous— passes over the orbicular muscle, and then sinks in the corrugator. Its branches are, a. A Superciliary Branch—distributed to the eye- brows and muscles; and inosculating with the temporal and lachrymal arteries. 0. A Superficial Frontal Branch—extensively dis- tributed on the glabella, and rising as high as the fontanelle or bregma. y. A Deep Frontal Branch—lying under the mus- cles, and distributed to the pericranium by many ramuK, some running externally, and others more internally. F. Minute branches, rising separately from the trunk, and distributed to the optic nerve, the infundibulum, the pituitary gland, and the lower part of the plexus choroides. G. The communicating artery.—This, along with the deep branch of the vertebral artery of the cerebrum, forms the circle of Willis. It is tortuous; but when it leaves the tunica arachnoides, proceeds in a straight line back- 32 BRANCHES FROM THE Sect. I. wards and inwards, along the sides of the cor- pora mammillaria, near the infundibulum, where it reaches the artery already mentioned, and there forms an obtuse angled quadrangular space. It varies in size, and sends a. Branches to the corpora mammillaria. b. Branches to the infundibulum. c. Branches to the optic nerve. d. Branches to the crura cerebri, inosculating with the posterior carotid. H. The ANTERIOR CAROTID ARTERY, Or ARTERIA callosa.—The internal carotid, at that place where the anterior lobe of the brain is separated from the posterior, divides into two branches of nearly equal size; of which the anterior pro- ceeds immediately inwards, and a little for- wards; then bends above the corpus callosum, between the hemispheres, to the posterior lobes of the brain: In which course it gives u. Branches to the optic and olfactory nerves. fi. Many branches, winding outwards to the ad- joining anterior lobes of the brain. y. A Communicating Branch—inosculating with its fellow of the opposite side. This branch is short and transverse, and sends -f- A branch to the anterior part of the third ven- tricle. + +A branch to the fornix, the anterior com- missure, and the septum lucidum. + + + Branches to the pia mater, lining the neighbouring part of the cerebrum. 3. Branches to the inferior side of the anterior lobe, and to its flat and internal surface, where Sect. I. ARCH OF THE AORTA. 33 the falx separates the two hemispheres. They run in circuitous windings, penetrate deeply the substance of the brain, and in many places inosculate with the posterior carotid. c. Many branches to the corpus callosum and ad- jacent cerebrum, sinking into the posterior lobe, forming inosculations with the posterior carotid and vertebral arteries, and extending even to the tentorium. I. The posterior carotid, or the artery of the fossa sylviana.—This second division of the trunk enters the fossa Sylvii that separates the anterior and posterior lobes,* and gives to each numerous superficial branches, spreading on the circumvolutions of the cerebrum, and several deep ones, ramified backwards. a. Branches to the optic nerve and choroid plexus, b. Branches to the pia mater, covering the basis of the brain. c. Numerous branches, inosculating with the ra- muli of the former trunk and vertebral artery, and amongst themselves entering into various anastomoses. ♦ Murray assigns only two lobes to each hemisphere. 34 BRANCHES FROM THE Sect. J. DISTRIBUTION OF THE SUBCLAVIAN ARTERY AND ITS BRANCHES. The same division is common to the branches of the right and left subclavian arteries; but they so far differ, that the right subclavian is much larger, passes obliquely over the trachea, and sends off the common carotid. Having left this branch at the side of the trachea, it is now more properly the right subclavian; and, still continuing larger than the left, proceeds nearly in a transverse direction. The left subclavian, on the other hand, while it gradually ascends from the inclining part of the arch, passes on to its place of destination with a more rapid and extensive curvature. These two arteries run in such a direction, above the superior margin of the first rib, as to be concealed for some time by the clavicle. They then proceed, with the brachial plexus, across that space lying between the first and second scalene muscles; and, being covered by the flattened ex- tremity of the clavicle and the pectoral muscle, bend to the axillae, where they take the name of Axillary Arteries. The branches of the subclavian arteries, and their ramuli, present so many varieties Sect. I. ARCH OF THE AORTA. 35 that no description, either as to their number or their direction, can in every respect correspond with Nature. In general, however, the four first branches arise before the artery sinks under the scalenus, while the rest are sent off beyond the margin of this muscle. These are, A. The internal mammary artery—going off from the lower and anterior part of the trunk, at the highest part of the pleura, where, ascending gradually, and again bending down- wards to the sternum, it reaches the margin of the first rib, under which it passes; and, run- ning between the pleura and middle part of the cartilages of the ribs, descends between the in- ternal intercostal and the sterno costal muscles, as far as the diaphragm. It then passes between the diaphragm and the ribs, and, dividing into many twigs, is lost under the rectus of the ab- domen. From its origin to the third rib, it bends towards the sternum, then gradually in- clines outwards. Its branches are, a. A Recurrent Branch—passing in the direction of the clavicle to the muscles of the neck, and distributing to these muscles small irregular ramuli. b. The Thymic Branch—which is often double, and varies very much in the distribution of its twigs to this gland; which also receives arteries from those of the mediastinum and pericardium. c. A branch accompanying the phrenic nerve— of small size, supplying the neighbouring 36 BRANCHES FROM THE Sect. I. parts with twigs, and afterwards uniting at the diaphragm with the phrenic artery of the aorta. d. The Superior and Posterior Pericardiac Branch —rising sometimes from the mammary, and sometimes from the subclavian artery; some- times from the aorta or from the common carotid; and as it winds to the upper and back part of the pericardium, distributes itself upon the trachea, the glands, the coats of the pul- monary artery, the pericardium, and oeso- phagus. e. Many Mediastinal Branches—rising between the third and sixth ribs; some of which go to the thymus gland, and a larger one to the diaphragm. f. Sternal Branches—spreading variously on the back of the sternum, and uniting with branches from the opposite side. g. Smaller branches to the pericardium and glands, lying on the vena cava. h. Many branches to the adjoining surface of the LUNGS. i. Many branches going outwards, entering the intercostal spaces of the six superior ribs; the first of which are bent to the sternomastoid, the sternohyoid, and the sternothyroid. Others form, at each interstice of the ribs, along with the thoracic and intercostal arteries, double inosculating rings; and others, arising from these annuli, go to the intercostal and pectoral muscles, the mammae, the obliquusdescendens, and the skin. Sect. I. ARCH OF THE AORTA. 37 k. The Phrenico-pericardiacBranch—descending above the pericardium to the diaphragm, and sometimes stretching near the ensiform car- tilage to the rectus muscle. /. The Musculophrenic—rising in a large branch at the sixth interstice of the ribs, turns out- wards, between the cartilages and the sterno- costal; then proceeds obliquely to the inter- stices of the seventh, eighth, and ninth ribs, where it forms inosculating rings with the in- ferior intercostal arteries; and here sending many twigs to the diaphragm, at last spreads at the tenth rib on the transverse muscle of the abdomen. m. A branch, winding on the surface of the ensi- form cartilage, and inosculating with the branches of the opposite side, or going down as far as the rectus muscle. Sometimes passes through the ensiform process. n. The Epigastric Branch.—A continuation of the trunk: as it leaves the thorax by the side of the ensiform cartilage at the seventh rib, is covered by the abdominal muscles, and divided into a. An Internal Branch—going down to the rectus muscle, often as far as the' umbilicus, and in- osculating with twigs of the epigastric. (i. An External Branch—going to the transversalis, and inoscidating with the epigastric, intercos- tal, and lumbar arteries; sometimes sent from the musculo-phrenic; and if that be smaller, this supplies it with many brandies. B. The inferior thyroid, or anterior cer- vical artery—rising from the fore part of the trunk, near the mammary and vertebral H 38 BRANCHES FROM THE Sect. I. arteries; and being covered by the sternomastoid, and bent a little upwards and outwards, imme- diately divides into four principal branches— 1. The Transverse Scapular—the lowest branch of the thyroid artery, but sometimes of consi- derable size—is covered at first by the sterno- mastoid, and passes transversely to the scapula, under the trapezius. The superficial cervical sometimes supplies the place of its superior scapular branch. a. Branches going separately to the sternomastoid, the sternohyoid, the omohyoid, and the subcla- vian muscles, the coats of the arteries and veins, and the skin of the neck and breast. b. The Superficial Scapular Branch—giving twigs to the integuments on the top of the shoidder and surface of the trapezius and deltoid. e. Branches to the posterior part of the trapezius. d. Branches to the levator scapulae, and the ser- ratus. Thus is the artery often wholly expended. At other times, it sinks deep under the trapezius, in many tortuous windings, where it properly takes the name of superior scapular, or dorso» scapulars and is chiefly divided into two smaller trunks, sending previously off a. Branches to the subclavian and adjoining part of the trapezius muscle. t>. Branches to the lesser portion of the serratus major anticus, and adjoining rhomboid, near the superior angle of the scapula. y. A branch, running upon the surface of the su- praspinal to the concave side of the acromion; inosculating, near the coracoid process, with the humeral thoracic of the axilla, and again Sect. I. ARCH OF THE AORTA. 39 communicating, at the superior angle, with the superficial artery of the base. t. Abranch, passing over the outer surface of the spine of the scapula; and, after giving twigs to the bone and the neighbouring muscles, inos- culating with the inferior circumflex scapular in the infraspinal cavity. Under the Trapezius, it divides into a. The Superspinal—the first branch of the divided artery, passing through the semilunar notch, and distributing many twigs to the supraspinatus, is continued onwards, in two branches, under the acromion process and supraspinatus, where it begins to send branches to the scapula itself, the capsular ligament, the infraspinatus, the teres minor, and at last inosculates with the inferior circumflex scapular. b. The Superficial Branch of the base of the Sca- pula—larger—proceeds near the lower part of the levator scapulae to the base, and, going down between the serratus major and the rhom- boid, reaches the inferior angle of the scapula. In this course, it gives many branches to the rh/>mboid and serratus; and through them to the trapezius, the serratus posterior, the skin, and subscapular muscle: afterwards forms, near the inferior angle, with the inferior scapular branch, a beautiful circle upon the surface of the serra- tus; from which branches descend to the latis- simus dorsi. Thus does the above remarkable artery, as well as the superspinal, arise often from the superior or dor so-scapular. I have observed, however, that the transverse scapular sometimes sends off the superspinal branch only, and that the other proceeded from the superficial cervical artery. 40 BRANCHES FROM THE Sect. I. 2. The Transverse Cervical—running, by the side of the neck, transversely and upwards, to the cervix, where it is concealed by the trapezius. Its various branches sometimes arise from the superficial cervical artery. a. Branches to the sternomastoid and skin. b. Branches to the trapezius, levator scapulae, and splenius. c. A large branch, ascending between the splenius and trapezius, giving r. muli to both these and the complexus, and at last inosculating freely amongst the muscles with the descending branch of the principal occipitocervical artery. d. A branch, descending to the trapezius, rhom- boid, complexus, and supraspinatus muscles, and inosculating with the superficial cervical and the transverse scapular branches. 3. The Ascending Thyroid Artery—rising be- tween the rectus anterior and scaleni muscles, upon the fore-part of the transverse processes, as high as the second vertebra; varying in size and in the number of its branches. It exhibits _L Superficial branches. From which a. Branches are sent, transversely and outwards, to the angularis, splenius colli, sternomastoid, and scaleni muscles. b. Branches to the rectus, winding variously on the anterior surface of the vertebrae. c. Branches to the tenth pair of nerves and the ganglion olivare; inosculating with the pha- ryngeal artery. -f -j- Deep branches, which are sunk between the vertebral interstices as the artery ascends. Of these are reckoned, a. Branches to the intertransversarii, scaleni postici, and the origin of the splenii muscles. Sect. I. ARCH OF THE AORTA. 41 b. Branches passing through the openings for the intercostal nerves to the involucra of the spinal marrow, and inosculating with twigs of the vertebral artery. 4. The Thyroid Branch of the Thyroid Artery.— In this the whole trunk is expended. It bends under the carotid to the side of the larynx; and, after repeated windings, reaches the inferior part of the thyroid gland. It sinks into the gland; and, while it divides into many ramifi- cations, is partly distributed to the whole gland, and partly inosculates with the superior thyroid. It gives, 1. Lesser branches to the outer muscles of the os hyoides and larynx, to the superior cartilages of the trachea, and the inferior thyroid gan- glion. Of these, the branches which go to the larynx form the inferior laryngeal. 2. Pharyngeal branches to the inferior constrictor muscles, the oesophagus, and the posterior mus- cles of the larynx. 3. The Superior Tracheal or Thoracic Branch- often double or triple. One of the branches, descending with the trachea into the cavity of the thorax, and there forming above the tra- chea a beautiful plexus, communicates with the inferior bronchial and the higher intercostal branches. C. The superior intercostal artery—rises more externally than the vertebral, from the upper and posterior surface of the trunk; then ascends with it to the hollow that is formed by the anterior scalenus, the surface of the first rib, and bodies of the vertebrae. It is there suddenly reflected; and, proceeding to the 42 BRANCHES FROM THE Sect. I. roots of the first and second ribs within the thorax, gives, a. Ascending branches, irregular in number and size, to the scaleni, the longus colli, and the nerves. b. Branches to the intercostal muscles of the first and second interstices, which run along the margins of the ribs, forming circular inoscula- tions with the higher thoracic branch and the branches of the internal mammary. c. Numerous Oesophageal Branches—inosculat- ing with the superior tracheal branch of the thyroid artery. d. Branches sent through the openings for the nerves to the hollow of the spine, and there distributed both to the involucra and the me- dulla. e. Branches passing over the third rib, and inos- culating with twigs of the first inferior inter- costal. f. Deep branches, passingthrough the intercostal spaces to the deep muscles of the back and neck. D. The vertebral artery—larger than the former, rises from the superior side of the subclavian; and, ascending a little backwards, covered by the ganglions of the intercostal and the cellular membrane, reaches the perforations of the transverse processes of the cervical ver- tebrae. Through these it penetrates, and, rising perpendicularly from the sixth, or sometimes from the fifth or fourth opening, reaches the aperture of the atlas, where it bends a little ARCH OF THE AORTA. 43 outwards; and havingpassed through, undergoes another more extensive flexion backwards and inwards, by which it is carried transversely in a groove, between the occipital bone and the atlas, to the foramen magnum. Through this open- ing, having at last entered the cranium, it pro- ceeds upwards and forwards, and at the basilar apophysis, under the.medulla oblongata, meets, at an acute angle, with the vertebral artery of the opposite side, forming the basilar artery to be distributed to the cerebrum and cerebellum. It gives, in this course, 1. Lateral branches to the muscles between the transverse processes, and others, near to the vertebrae. 2. Larger branches, passing through the inter- vertebral openings for the nerves, to the cover- ings of the medulla, and inosculating with the anterior and posterior spinal branches. 3. A branch going, with various twigs, from the first bend of the artery to the rectus posticus major and minor, the obliquus major and mi- nor, the trachelomastoid, and complexus; and inosculating with branches reaching from the occipital artery. 4. Posterior Meningeal Branches—proceeding from the second and third flexures, and wind- ing forwards upon the dura mater of the cerebellum, as far as the clinoid processes and receptacle, and backwards towards the occiput. Before the formation of the basilar artery, there are sent off in the cranium itself— BRANCHES FROM THE Sect. I. 5. The Inferior Artery of the Cerebellum—.issuing at a right angle from the trunk, near the me- dulla oblongata, between the tenth and acces- sory nerves. It not only distributes many branches to the lower surface of the cerebel- lum, but, being concealed between the medulla oblongata and the crura of the cerebellum, is so bent backwards and upwards, as to terminate in the vermiform process of the cerebellum and fourth ventricle. In this course are given, 1. Branches to the tenth and eleventh nerves. 2. Branches to the anterior and lateral surfaces of the medulla oblongata, and corppra olivaria. 3. Branches to the posterior surface of the me- dulla oblongata, and the choroid plexus of the fourth ventricle. 6. Branches sinking into the furrow that sepa- rates the corporapyramidalia from the tuber annulare. 7. The Posterior Spinal Artery—rising often from the inferior artery of the cerebellum; and, bending from the anterior to the posterior sur- face of the medulla oblongata, descends tortu- ously on the spinal marrow, and inosculates freely in its descent with its fellow and with other branches, as they pass to the medulla through the openings for the nerves. It ter- minates on the surface of the medulla at the second lumbar vertebra; and through its whole course supplies, with minute twigs, the me- dulla, and its several nerves, as they pass out. 8. The Anterior Spinal Artery—rising, at an acute angle from the trunk, near its fellow, and, descending in a retrograde course, pro- Sect. I. ARCH OF THE AORTA. 45 ceeds in a winding direction upon the anterior surface of the medulla, inosculating by trans- verse branches in the region of the neck and back with the artery of the opposite side, to which it is parallel. The two arteries at last uniting near the termination of the medulla, form a trunk, which is sent to the extremity of the os sacrum; and which, if emptied of its blood, assumes the appearance of a nerve: whence the ancient error as to a JVervus Azygos. It distributes numerous branches to the neigh- bouring parts, and to the nerves as they go out, and enters into frequent anastomoses with the spinal branches, penetrating the inter- stices of the vertebra*. The basilar artery, being formed as above, occupies the depression in the middle of the tuber annulare, and at its anterior part divides into four parallel branches, proceeding from the trunk at right angles. Of these, the posterior go to the cerebellum; and the two anterior, ramified on the cerebrum, unite with the com- municating arteries of the carotid, and form the Great Circle of Willis. From the trunk a. Many branches proceed, transversely and out- wards, distributed to the surface of the me- dulla oblongata, the corpora olivaria and pyra- midalia, the tuber annulare, the inferior sur- face of the cerebellum, and the neighbouring pairs of nerves. Of these, abranch, accompany- ing the auditory nerve, passes to the labyrinth of the ear. *. The Deep Arteries of the Cerebellum—Right I 46 BRANCHES FROM THE Sect. I. and Left—winding behind the crura of the i cerebrum to the superior part of the cerebel- lum, and there exhibiting, _J_ A Short Anterior Branch—distributed to the crura cerebelli, the cerebellum, the vermiform process and the choroid plexus, lying on the thalami. -\- _f- A Middle Branch—winding extensively on the upper side of the cerebellum; inosculating freely with the inferior of the cerebellum; en- tering the different sulci, and supplying the thalami, nates, testes, and pineal gland. _}. _j_ _L A Deeper Branch—following the same course; spreading, with minute twigs, on the crura cerebri, the thalami, nates, pineal gland, choroid plexus, the processes of the cerebellum at the testes, the valve of Vieussenius, and the fourth ventricle. r. The Deep Artery of the Cerebrum—-larger than the last, and separated from it by the third pair of nerves. Turns upwards along with the former, between the cerebellum and posterior Jobe of the cerebrum; and gives, 1. Smaller branches, running to the bottom of the third ventricle, the thalami, optic nerve, the mammillary eminences, the corpora quadrige- mina, and fornix. 2. Communicating Branches—forming the circle of Willis, %id frequently of unequal size. They proceed forwards, almost at a right angle, to meet the communicating artery of the carotid, and give minute twigs to the adjacent parts. 3. A branch, going to the sides of the crura of the cerebrum and the lateral ventricle, and distri- buting small branches above the thalami, to the corpora quadrigemina, the pineal gland, the cho- Sect. I. ARCH OF THE AORTA. 47 roid plexus covering these parts, to the fornix, the corpora striata, and the third ventricle. 4. A branch, the greatest part of which is sent, im- mediately with its very numerous twigs, into the sulci of the posterior lobe; from which, again, smaller ramifications arise, to be distri- buted, as in Number 3d, to the corpus callosum and septum lucidum. 5. Branches, representing the continuation of the trunk, and inosculating with ramuli of the ca- rotid. E. The deep, or posterior cervical artery— Irregular in its origin, size, and extent, and, like the superficial cervical, or transverse sca- pular of the thyroid, spreads, sometimes more, and sometimes less extensively, with its branches. I have sometimes observed it the smallest of all, and proceeding from the superior intercostal. It generally issues from the subclavian, beyond the margin of the scalenus, though sometimes sooner under this muscle. Itthen winds upwards and backwards, between the deep muscles of the neck and the sixth vertebra; and is at last so dis- persed among the muscles, as to bestow its ultimate branches on the complexus, near the occiput. It usually gives, a. Branches winding on the surface of the bodies of the vertebrae. b. Branches distributed to the scaleni muscles. c. Branches to the spinal muscles of the neck, the trachelomastoid, splenius, and intertrans- versarii. d. Branches to the complexus, often interwoven with the occipital branches. 48 BRANCHES FROM THE Sect. I. D.The superficial cervical—rises about half an inch, or an inch from the first scalenus, at the upper and anterior side of the subclavian where it begins to bend downwards; imme- diately hides itself among the brachial nerves; and, spreading out afterwards, towards the superior costa of the scapula, divides into many irregular branches. Of these, the most remark- able are, -f- Branches distributed amongst the scaleni and brachial nerves. -j- -J- A Transverse Branch—bending upwards under the levator, and sending superficial branches to this muscle, the trapezius, and skin, and deeper ones to the splenius and com- plexus. If larger than usual, it runs in the di- rection already mentioned, and sends out either the superspinal or the superficial of the base of the scapula. It generally forms many anasto- moses with the branches of the thyroid and the deep cervical. distribction'of the axillary artery. The Subclavian Artery, as it bends from its first situation, between the breast and scapula, to the humerus, assumes the name of Axillary. Passing out, under the arch of the clavicle, it is sur- rounded by the nerves of the brachial plexus, the veins, glands, and a quantity of fat; lies in the Sect. I. ARCH OF THE AORTA. 49 hollow of the axilla, between the subscapular and serratus major; and, protected externally by the pectoral muscles, it soon approaches forwards to the arm and the interior margin of the biceps. At last, proceeding from the axilla to the inferior border of the tendon of the latissimus dorsi, it takes the name of Humeral Artery. It sends off, A. Small branches to the scalenus, first rib, coracoid process, the adjacent muscles, and nerves. B. The highest thoracic branch—arising above the second rib, or at the inferior margin of the first, and distributed in the upper region of the thorax, between the serratus and small pectoral—divides into, + A Transverse Ascending Branch—covered by the serratus, to which it sends a recurrent twig, and inosculates twice or thrice at the first interstice of the ribs with the internal mammary and superior intercostal. -f -f A branch, going down beyond the second and third interstices, and at last receiving some twigs of the long thoracic. From this proceed, a. A large branch to the serratus magnus. b. Two branches, uniting at the second intercostal space with the internal mammary and intercostal. c. Two branches to the third interstice, where this ramus generally terminates. d. Branches to the pectoral muscles and skin. C. The long, or superior thoracic, or ex- ternal mammary—running down as far as 50 BRANCHES FROM THE Sect. I. the fifth costal interstice. It sometimes arises from the circumflex, or from the inferior scapu- lar. tt. Branches to the glands of the axilla and mam- ma, running sometimes to the nipple. /3. Many branches, irregular in series and situa- tion, to the serratus major and minor; and, passing the second and fourth interstices, to the great pectoral and mamma, anastomosing with the highest thoracic. y. Branches sinking deeper, forming double cir- cles with the internal mammary and the in- ferior intercostal, as low as the interstice of the fifth rib, and sending branches to the inter- costal muscles. D. The humeral thoracic—rising from the anterior part of the trunk, between the second rib and the coracoid process, to the upper margin of the lesser pectoral; penetrates the in- terstice of the deltoid and pectoral muscles; and in its course sends, a. A deep branch to the serratus major. b. Branches to the deltoid, to the great pectoral and subclavian muscles, and rising, above the clavicle, to the neck. c. A branch, running along the subclavian muscle to the pectoral; and, in the space between this and the deltoid, distributing its branches to the pectoral muscle, the clavicle, and skin, and at last inosculating with the transverse scapular. d. Another branch to the pectoral and deltoid. e. A branch, near the coracoid process, descend- ing to the axillary glands. Sect. I. ARCH OF THE AORTA. 51 /. A Circumflex Branch—winding backwards, under the muscle, round the origin of the deltoid. From which proceed, -j- A Cutaneous Descending Branch—attending the cephalic vein, and terminating at the top of the humerus and the pectoral muscle. -j- -{- A Superficial Branch—passing along the outer edge of the deltoid, and the adjoining margin of the acromion. -f- -j—\- A Deep Branch to the articular capsule, the coracoid process, and the deltoid. -\- -J—\- -\. A branch to the spine of the scapula, uniting with the superspinal thyroid and the posterior axillary circumflex. E. The alar thoracic.—This artery is some- times wanting, though at other times it is large, and sends numerous branches to the axillary glands, and some also, spreading extensively in various directions, to the subscapular, pectoral, and serratus. N. B. The number and distribution of the tho- , racic arteries are so irregular, that anatomists have sometimes enumerated six separate trunks distributed to the thorax. F. Two or more large branches, rising near the upper and inferior margin of the scapula, send- ing twigs to the nerves, serratus, levator scapulae, latissimus dorsi, and particularly the subscapular; inosculating, partly with the super- ficial thyroid scapular of the base, and partly disappearing among the muscles. G. The inferior scapular, or infrascapu- lar, or subscapular—rising at the inferior 52 BRANCHES FROM THE Sect. I. margin of the subscapular muscle, divides into conspicuous branches, which run in various directions. Arises, also, sometimes among the thoracic branches, when, bending downwards, it sends «,. A branch to the surface of the subscapular, the capsular ligament, and the muscles at- tached to the coracoid process. fl. A Deep Branch—winding, with its twigs, through the subscapular to the naked scapula, after giving twigs to the teres major and latis- simus dorsi. y. A Muscular Branch—large, and sometimes rising separately. Sending branches to the sub- scapular, extending as far as the base of the scapula; and distributing extensively large branches to the teres major, the serratus, the latissimus dorsi, and axillary glands. 3. A Conspicuous Branch—running closely along the margin of the subscapular, and forming, at the inferior angle of the scapula, which it tra- verses, a large circle with the superficial thy- roid scapular of the base. It rises sometimes from the muscular branch. e. A branch, parallel to the inferior costa, and ex- tending to the teretes, the long extensor, and the glands. JV. B: All these branches present frequent varia- tions, and often distribute more ramuli, which, for the sake of conciseness, I omit. £. The Scapular Circumflex.—The branches al- ready enumerated having supplied the inner Sect. I. ARCH OF THE AORTA. 53 part of the scapula, this large trunk bends be- tween the inferior costa of the scapula and teres major, to the intraspinal cavity, near the cervix, and proceeds, under the teres minor and infraspinatus, to the spine; giving -j- Branches to the teretes