Description of an Ancient Anomalous 
Skeleton from the Valley of Mexico; 
with Special Reference to Supernume- 
rary and Bicipital Ribs in Man. 
Dr. Ales Hrdlicka. 
AUTHOR’S EDITION, extracted from BULLETIN 
OF THE 
ipuseata ot Natural gtstov^ 
Vol. XII, Article V, pp. 81-107. v 
New York, May ij, iBgg. / 
106 E. 71ST STREET. NEWYORK. Article V. —DESCRIPTION OF AN ANCIENT ANOM- 
ALOUS SKELETON FROM THE VALLEY OF 
MEXICO ; WITH SPECIAL REFERENCE TO SU- 
PERNUMERARY AND BICIPITAL RIBS IN MAN.1 ■ 
Dr. Ales Hrdlicka 
The skeleton described in this paper was exhumed at the 
adobe-works at St. Simon Tonaguac, a small suburb of the City 
of Mexico. The same place has yielded from time to time 
human bones and various objects of archaeological interest. The 
bones were procured directly from the workmen by Dr. Carl 
Lumholtz during his explorations for the American Museum of 
Natural History, and are now in the Anthropological Department 
of the Museum (Catalogue No, £-%-%). 
The skeleton was discovered about three metres below the sur- 
face. The workmen were unable to give definite information 
regarding the surroundings of the bones. The importance of the 
skeleton induced me to make, on my recent visit to Mexico,2 a 
special examination of the adobe-works about St. Simon. 
St. Simon lies about a mile and a half northeast from the City 
of Mexico, to the left of the road which leads to Guadalupe. 
Most of the inhabitants of this little town, as well as those of 
several small settlements adjoining, are occupied with adobe- 
making. The grounds of St. Simon are part of the lowlands 
which extend from the City of Mexico to the Lake of Texcoco. 
In places the ground rises slightly over the level of the lowlands, 
and here most of the excavating is done. 
The adobe deposit consists of a rather compact dark gray 
earth. Originally it was probably marsh land, which has been 
covered with material derived from successive inundations. 
Mixed with this is the accumulated refuse from habitations, which 
contains many fragments of pottery, pieces of obsidian, and bones 
of animals. 
The particular place from which the skeleton came is at a rise 
1 Read in a preliminary form before the American Association for the Advancement of 
Science, August 13, 1897. 
2 Lumholtz-Hrdlicka Expedition, under the auspices of the American Museum of Natural 
History, New York, March-July, 1898. 
[May, iBgg.~] 82 
Bulletin American Museum of Natural History. 
[Vol. XII, 
of about two metres above the level land, and is about seventy 
metres in its greatest length. Its characteristics are identical 
with those of the other adobe-works of St. Simon. I could dis- 
tinguish no regular stratification in the earth of this place, nor any 
difference in its composition at different heights. The deeper 
parts look darker and even black ; but this is due to difference 
in moisture. About four metres below the highest point of the 
surface, water is met toward the end of the dry season. This 
prevents further digging downward. 
Throughout the deposit, but particularly in its upper third, 
numerous layers of fragments of pottery are found. These layers 
do not form continuous strata, and when exposed from the top 
look like larger or smaller irregular heaps of fragments. In all 
probability they represent dumps of refuse, Down to two 
metres and a half from the top, I found individual animal bones 
in these layers of potsherds, or in the earth between them. Below 
this the deposit is less productive of remains of all kinds, and 
the fragments of pottery are much more scattered. At a depth of 
three metres and below, numerous human skeletons are met with, 
and occasionally stone'beads, terracotta, and stone figures are 
found. The skeletons lie singly. The archaeological objects 
belong apparently to the Aztec culture. 
The anomalous skeleton comes from this lower portion. Dur- 
ing my stay in the City of Mexico, I obtained about fifteen addi- 
tional skulls and skeletons from the same place and depth. 
Among these skulls or skeletons, so far as I can say from a pre- 
liminary examination, there is not one that approaches in inferior 
characteristics the specimen here described. 
I gave a certain amount of attention to the fragments of pottery 
found at different horizons in the adobe deposits of St. Simon. 
My observations, which are not those of a trained archaeologist, 
may be summed up as follows. In no portion of the deposit, to 
the depth of four metres, do fragments of any one kind of pottery 
predominate to the complete exclusion of other kinds. Many of 
the fragments found, from the surface down to a depth of 1.5 
metres, are of very smooth, polished ware of a bright red color. 
Numerous other fragments from this same part show various 
drawings in colors, and still other fragments have stamped or 
incised designs. At the same time, there are frequently found, 1899-] 
Hrdlicka, An Ano7nalous Skeleton from Mexico. 
83 
among these fragments of high-grade pottery, pieces of very rude 
earthen vessels, thick, rough, and without any decoration what- 
ever ; also crude potsherds showing impression of network with 
which they were surrounded. Lower down, the higher grades of 
fragments become rare and the crude fragments more frequent, 
I myself dug out, however, a fragment of the red, highly polished 
pottery from over two metres below the surface ; and at a depth 
of from three to four metres I took out half of a fine Aztec 
tumbler, and saw an entire one dug from the same layer. These, 
however, may have been buried there. 
Obsidian fragments are met with throughout the whole deposit. 
They consist generally of crude fragments or pieces ; but occa- 
sionally parts of knives or chisels, or nuclei, are also found. 
Among the hundreds of obsidian fragments which I examined, I 
did not find an arrow or a spear point ; nor have the brickmakers 
whom I questioned on this point met with any.1 From my ob- 
servations on this particular adobe-field, I reach the following 
conclusions : 
The field is an old, gradual accumulation of aqueous origin, 
augmented by irregular heaps of refuse consisting mainly of frag- 
ments of pottery. The upper half, or a little more, of the deposit, 
corresponds to the period in which the best kind of Aztec pottery 
was made. The lower parts show a predominance of crude forms 
of earthenware, some of which may be of a pre-Aztec origin. 
About three metres from the surface of the mound begins what 
in all probability is a prehistoric burial-place. Judging from the 
pottery, figures, and ornaments buried here, and from the nature 
of the majority of the skulls recovered, this burial-place has 
been at least partly utilized by the Aztecs, 
The skeleton here described, as already stated, lay deep in the 
ground. It could not be ascertained if any ancient manufactured 
objects were found in its immediate vicinity. Other skulls from 
the same locality were secured at the same time by Dr. Lumholtz. 
About half of these agree in appearance, to a certain extent, with 
the skull of the skeleton in question ; while the other portion 
differs. Several of this latter class show signs of incineration. 
1 Some of the important adobe-fields around the City of Mexico have received the attention 
of Professor William H. Holmes of the National Museum in Washington. His two notes 
on these deposits are published in the Transactions of the Anthropological Society of Wash- 
ington, 1885, pp. 69, 70, and in Ancient Cities of Mexico, 1897, p. 299. 84 
Bulletin American Museum of Natural History. 
[Vol. XII, 
Most of the skulls I obtained from the same locality also agree in 
appearance, to a certain extent, with the skull of this skeleton. 
But, as already mentioned, there is not one among the skulls or 
skeletons from this locality, and now in the possession of the 
Museum, which approaches this specimen in inferior character- 
istics. All the parts of the skeleton, and most of the other bones 
from the same place, are fairly well preserved. The bones con- 
tain but little organic matter. 
The skeleton is not complete. Three of the vertebrae (sixth 
cervical, last dorsal, and first lumbar), both ulnas, several teeth, 
and most of the small bones of the hands and feet, are missing. 
Not one of the parts present shows any pathological changes. 
The general characteristics of the bones of the specimen, taken 
together, indicate that we have to deal with the skeleton of an 
adult though not very aged man of moderate muscular develop- 
ment and of rather small stature. 
The skull is of small size, and somewhat deformed. The de- 
formity is of the kind which Topinard terms ‘ simple occipital.’ 
It consists, in this case, of a flattening, slightly greater on the 
right, of that part of the occiput which is situated between the 
external occipital protuberance or inion, and the parietal foramina 
or obelion. The same deformation may be seen in a few other 
male skulls from the same locality. I have also occasionally 
found the same type among skulls of prehistoric peoples of other 
parts of Mexico. It is the type of deformation of the old mound- 
builders, pueblos, and cliff-dwellers, but not carried to the ex- 
treme. Waitz mentions,1 that, in many of the Indian tribes, the 
flat-backed heads were produced artificially by means of a special 
form of the infant’s cradle, or of what served in place of it. 
In size the skull does not reach that of an average male adult 
of the white race. The thickness of its parietal bones below the 
parietal bosses ranges from 3.5 mm. to 4.5 mm., a proportion 
common in the whites.2 
The forehead is well arched, and fairly high and broad, having 
a minimum frontal diameter of 9 cm. Its aspect, however, has 
been affected by the occipital compression. The sagittal region 
1 Anthropologic der Natur-Volker, IV, p. 62. 
2 The subject, calculating his height from the long bones by Manouvrlere’s Tables, measured 
about 1.6 metres. 1899.] 
IJrdlicka, An A nomalous Skeleton from Mexico. 
85 
is high, oval from side to side, and presents no marked ridges or 
depressions. The parietals are full, and the right side shorter 
than the left. The temporal regions are about as concave as in 
an ordinary white mesocephalic skull. The temporal ridge is 
from 5 mm. to 8 mm. broad, and well marked ; approach of its 
upper edge to the bregma, along the coronal suture, is 7.1 cm.; 
the closest approach of its upper edge to the sagittal suture is about 
4.5 cm. Both these distances are smaller than in the average 
white.1 The occipital region is compressed. The occipital 
ridges and depressions are rather feeble, the crest being low and 
not very distinct. The mastoids are strong and of a good size, 
though not excessive. The supramastoid elevations are about 
medium. 
Of the facial parts the supra-orbital ridges are about as large 
as those in an average adult male white, or perhaps slightly larger. 
The glabella is convex and full. The malars are prominent, but 
not of excessive strength or size. They show no trace of any 
division. The zygomse are moderately massive, the maximum 
bizygomatic diameter being 12.8 cm. This is low in comparison 
with measurements of Mexican Indians from other localities. 
The canine fossae are of medium depth. The nasal-root depres- 
sion is small ; the nasal bridge, low and concave ; and the nasal 
bones, narrow. The nasal aperture is pyriform, and not very 
large. The nasal spine is quite strong and of medium height, 
being .9 cm. long. The nasal notches are well defined, the left 
slightly lower. There are no gouttilres simiennes (subnasal de- 
pressions). On both sides of the face the lachrymal bone enters 
into the formation of the lower border of the orbit ; on the right 
side it descends externally more than 2 mm. below it. A suture 
runs from each of the infra-orbital foramina to the edge of the 
orbit, and along the floor of this to the posterior opening of the 
infra-orbital canal. 
The dental arches are strong, though not massive. The upper 
arch is somewhat irregular externally and on the right. This 
irregularity consists of a greater depression over the incisors, and 
a somewhat greater elevation over and behind the canine, and is 
due to a vicious disposition of the dental sockets, to which I shall 
1 In a series of examinations of the skulls of whites, I found the distance of the upper border 
of the temporal ridges to range from s cm. to 7 cm., with an average of about 6.3 cm. 86 
Bulletin American Museum of Natural History. 
[Vol, XII, 
refer later. There is a certain amount of prognathism of 
the upper dental arch, but the face as a whole is orthognathous. 
(Plate I.) The lower jaw is of a peculiar shape, and is shown in 
Plate 11, Fig. i. I have found no other under-jaw of this type 
among the Mexicans, The bone is not very heavy, and is rather 
short. The angles are somewhat divergent, quite prominent, and 
externally irregular, which will be better seen in the front view 
Fig. i. Lateral Views of Lower Jaws; a, From Valley of Mexico ; b, Normal Male 
from Valley of ; c, Male Gorilla (Coll. Phys. and Surg.) ; d, Female Gorilla (Coll. 
Phys. and Surg.). 
(Plate 1). The chin is of medium prominence. The vertical 
ramus is relatively broad. But the most remarkable character- 
istics of this jaw are the form and relation of its processes and 
the form of the sigmoid arch they enclose. The coronoid process 
is distinctly higher than the condyloid, although our subject is 
not an aged person. The condyloid process is very short, which 
is more apparent on the specimen itself than on the figure ; and 
the sigmoid notch is much more open toward the front than 
toward the back. These characteristics of the upper extremity 
of the vertical ramus of the lower jaw are much more like those 
found in the Apes, particularly in the Gorilla, than in the human 
species. Fig. i is a stereographic drawing of this jaw, of two 1899-] 
Hrdlicka, An Anomalous Skeleton from Mexico. 
87 
jaws of adult Gorilla (reduced), and also of a normal jaw from 
the Valley of Mexico. 
The external auditory meati are small, measuring 4 by 7 mm. 
The retromastoid vascular foramina are large. This character- 
istic, combined with unusual smallness, or even absence, of the 
parietal vascular foramina, is almost constant in other skulls from 
the same location, while series of skulls from other parts of 
Mexico show this phenomenon only exceptionally.1 The base of 
the cranium is somewhat asymmetrical, which is the regular 
feature of skulls with occipital deformation. The bony processes 
of the base are of moderate strength. The left styloid is 2.7 cm. 
in length. The great wing of the left pterygoid process sends a 
slender, bony prolongation backward, which is almost met by a 
spicula of bone from the spinous process of the sphenoid bone ; 
the two forming a slightly incomplete pterygospinous foramen. 
Various degrees of this anomaly are found in the majority of 
skulls from the same locality, although it is exceptional in other 
parts of Mexico. (A tendency to the formation of pterygospb 
nous foramina is frequent in the whites.) 
The various nervous and vascular openings of the base show 
nothing special in size or disposition. The anterior lacerated 
foramen is smaller than in whites. The foramen magnum is 
somewhat irregularly ovoid in shape, the anterior part being the 
narrower. It measures 3.2 cm. in length by 2.9 cm. in breadth, 
with an index of g0.6. The posterior nares are well formed, and 
not more oblique than in whites. They are smaller in length 
than in breadth, their index reaching 105.9. This high index of 
the posterior nares is another characteristic of skulls from St. 
Simon Tonaguac. The petrous parts are slightly depressed 
below the level of the base. The glenoid fossae are of fair depth. 
The palate is slightly parabolical in outline, and normal. The 
dental arches are strong, without being too massive. 
Dentition has been completed. Most of the teeth are lost, ap- 
parently since death, as the alveoli show no signs of obliteration 
or absorption. The remaining teeth are of medium size, and 
normal in shape, but are set somewhat irregularly. The left 
upper and both lower wisdom teeth point almost directly forward, 
1 The inverse relation between the size of the retromastoid and the parietal vascular foramina 
is not uncommon. 88 
Bulletin American Museum of Natural History. 
[Yol. XII, 
and somewhat inward ; and on the right side of the upper 
alveolar process in front, we find a diastema between the first in- 
cisors • while the first bicuspid is situated over and a little behind 
the neighboring canine. 
In the interior of the skull, as far as this could be examined, 
there was found nothing special. The frontal crest is low.1 By 
Broca’s method, the capacity of the skull is 1270 cm. ; by 
Flower’s, 1225 cm. This is the lowest of the capacities of the 
male skulls from St. Simon. (Figs. 2-6.) 
Fig. 2. Norma Anterior 
Cranium 
Maximum anteroposterior diameter 
Maximum transverse diameter 
Cephalic index 3 
Height (basion-bregma) 
MEASUREMENTS OF SKULL.2 
‘The sharp crest situated in the median line on the ventral surface of the frontal bone 
differs, both in extent and height, in different individuals. In its extremes it may possibly 
prove a racial characteristic, though never one of prime value. 
2 The French methods and nomenclature are followed throughout, unless otherwise in- 
dicated. 
3 These indices are of secondary value on account of the occipital deformation. The mean 
cephalic index of six male skulls from the same locality, with similar deformation, was 89.0 ; of 
three male skulls, without deformation, 80.0; of five female skulls, without deformation, 81.4. 1899-1 
Hrdlicka, An Anomalous Skeleton from Mexico. 
89 
Height-length index 82.7 
Height-breadth index 92.1 
Minimum frontal diameter. g.o cm 
Bistephanic diameter,.'. 11.0 cm 
Bi-auricular diameter (between points where temporal depression 
begins, above the roots of zygomse)... 11.2 cm 
Bimastoid diameter (between tips of mastoids) 9.8 cm 
Basion-alveolar point 8.9 cm 
Basion-nasion 8.8 cm 
Basion-bregma 12.9 cm 
Basion-obelion 10.8 cm 
Basion-lambda 9.75 cm 
Basion-inion 7-4 cm 
Arcs 
Maximum circumference above the supra-orbital ridges 47-9 cm 
Centres of external meati auditorii over forehead, above the ridges. 28.0 cm 
Centres of external meati auditorii over frontal eminences. 30.0 cm 
Centres of external meati auditorii over bregma. 32.5 cm 
Centres of external meati auditorii over maximum expanse of the 
cranial vault 33.3 cm 
Centres of external meati auditorii over lambda 26.6 cm 
Centres of external meati auditorii over inion 22.0 cm 
Nasi on-bregma 11.7 cm 
Nasion-inion 28.3 cm 
Nasion-opisthion 32.5 cm 
Nasion-ophryon (Topinard) 2.0 cm 
Face 
Chin-nasion diameter 10.9 cm 
Alveolar point-nasion diameter. 6.55 cm 
Bijugal diameter 11.5 cm 
Maximum bizygomatic diameter... 12.8 cm 
Facial index, alveolar Point ophryon height x 100 66.8 
’ maximum bizygomatic diameter 
Maximum diameter (exterior) of upper dental arch 6.5 , cm 
Bimandibular diameter (between elevations marking the union of 
posterior with anterior ramus) 8.1 cm 
Bigonial diameter 10.1 cm 
Height (nose) 4-45 cm 
Maximum width (nose) 2.4 cm 
Nasal index 1 (platyrrhine) 53.9 
Height (orbits) 3-35 cm 
Width “ (inner edge of lachrymal canal at dacryon point to 
maximum outer point) 3.70 cm 
Orbital index2 (megaseme) 90.5 
1 Average of nine male skulls from same locality, 50.4 ; of five females, 53.0. 
2 Average of nine male skulls from same locality, 90.6 ; of five females, 91.5. Bulletin American Museum of Natural History. 
[Vol. XII, 
Fig. 3. Norma Lateralis (j^). 
Fig. 4. Norma Posterior (29s93). 1899.] 
Hrdlicka, An Anomalous Skeleton f rom Mexico. 
Fig. 5. Norma Superior (j9^). 
Fig. 6. Norma Inferior (39s^). 92 
Bulletin American Museum of Natural History. 
[Vol. XII, 
Height (upper dental arch) from alveolar point to nasal point 2.0 cm 
Lower jaw (mentum to lower alveolar point) 3.4 cm 
Height of posterior ramus of lower jaw (coronoid process, 6.5 cm.; 
condyloid process, 6.0 cm.) 6.25 cm 
Length of anterior ramus of lower jaw 9.6 cm 
Depth of sigmoid notch of lower jaw ' 1.63 cm 
Angle 1160 
Thickness of lower jaw at symphysis 1.2 cm 
Thickness of lower jaw at second molars. 1.7 cm 
BONES OF THE BODY. 
VERTEBRAL COLUMN. 
Cervical Vertebra. 
Dorsal Vertebra. 
Lumbar Vertebra. 
Present 
6 (6th wanting) 
ix (12th wanting) 
4 (xst wanting) 
Conformation 
normal 
normal 
normal 
Spinous processes... 
Maximum antero- 
posterior diameter 
bicuspid to 5th 
resemble lumbar 
from xoth 
bodies broad excep t 
5th, which is of 
moderate breadth 
at middle 
Antero-posterior di- 
of 3d, 3.90 cm 
of 6th, 5.10 cm 
of 5th, 6.90 cm 
ameter of body.... 
Maximum lateral di- 
“ 1.40 cm 
“ 2.45 cm 
“ 2.90 cm 
ameter 
Maximum lateral di- 
“ 4.50 cm 
“ 5.40 cm 
“ 9.20 cm 
ameter of body.... 
Antero-posterior di- 
“ 1.75 cm 
“ 2.45 cm 
“ 4,50 cm 
ameter of canal.... 
Maximum lateral di- 
<■,, “ 1.40 cm 
“ 1-55 cm 
“ 1.35 cm 
ameter of canal.... 
S “ 1.85 cm 
“ 1.45 cm 
“ 1.90 cm 
Height (body) 
“ 1.10 cm 
“ 1.85 cm 
“ 2.75 cm 
Length of spinous 
“ 1.75 cm 
4.30 cm 
) “ 3.15 cm 
process (from notch) 
( “ 4.20 cm 
The bones are of rather sub-medium size and strength for a 
male, and differ in no important characteristic from the vertebrae 
of whites. 
Sacrum. 
This is composed of six segments ;1 but the sixth segment is 
somewhat rudimentary. The first body is only partly united to 
the rest of the bone. The lowest (fifth) pair of foramina is 
incomplete in the back. The inner curve of the bone is rather 
small, and commences below the third segment. 
1 The only two other sacra from the same locality, and now in this Museum, are each com- 
posed of six segments. 1899-] 
Hrdlicka, An Anomalous Skeleton from Mexico. 
93 
Maximum length of sacrum 12.6 cm 
Maximum breadth of sacrum xi.o cm 
Index of entire bone 1 87.2 
Index of bone, excluding sixth segment. 99.1 
Thorax. 
The constituents of the thorax of this skeleton are very remark- 
able, There are 26 ribs present, instead of 24, the usual number. 
By careful and repeated examinations, the characteristics of these 
ribs have been found entirely homogeneous, so that it is impos- 
sible to eliminate any pair as extraneous. Of these ribs 13 are 
right, and 13 left. They agree in color, form, and size. The 
skeleton, so far as we know, was found isolated, was kept together, 
and in the Museum it has since been kept separate. No question 
as to the identity of all the ribs with the skeleton has been raised 
by any one of the numerous scientists who have examined it. 
We have here a pair of supernumerary ribs. The question is, 
Which of the thirteen pairs is the supernumerary one? Exami- 
nation of the ribs alone does not satisfy us on this point. There 
are two pairs of floating ribs, as usual ; and none of the remaining 
pairs can be distinguished from the regular ribs. On examining 
the vertebrae, however, we find an articular facet on each side 
of the seventh cervical ; and a reconstruction of the upper part of 
the thorax demonstrates that the ribs begin at this vertebra, not 
at the first dorsal. There is no rudimentary or floating cervical 
rib. The first pair of ribs, although presenting an anomaly on 
one side, which will be described later on, has otherwise all the 
characteristics of the regular first dorsal ribs ; and in the same 
way all the following pairs of ribs resemble the corresponding 
regular pairs of the normal thorax. Granted that the two upper- 
most ribs are cervical, the condition is really then that of an ex- 
tension of the thorax upward, which is much more interesting 
than the existence of a rudimentary pair of cervical or other 
ribs. Sir William Turner, who on his last visit to the United 
States examined the skeleton, particularly the ribs, expressed the 
opinion that we have here a pair of cervical ribs articulating 
with the seventh cervical vertebra, and that all the thoracic 
1 This index is in the male European 112 ; in the female European, 116; in the Negro, 106; 
in the Australian, 99; in the Andamanese, 94 ; in the Orang, 87; in the Gorilla, 72. Sir 
William Turner : Journal of Anatomy and Physiology, XX, and Challenger Reports, Zoology, 94 
Bulletin American Museum of Natural History. 
[Vol. XII, 
structures, the blood-vessels included, were elevated, the extra 
cervical ribs assuming the anatomical relations which ordinarily 
belong to the first dorsal pair. 
The greater number of ribs, however, is not the only peculiarity 
in the case. Examination of the ribs of the left side shows the 
first and second ribs partly blended together. The spinal articular 
parts of both ribs are normal, though much closer together than 
they would be ordinarily ; and the bones continue independent 
for about 2 cm., at which point they gradually blend and form 
one rib. This shows no further marks of union, and is much 
broader and stronger than the first rib of the right side, which 
has a large single articular surface on the sternum, situated lower 
than the corresponding one of the other side. The third ribs are 
normal, and equal on both sides ; and none of the remaining pairs 
show any thing unusual. The maximum breadth of the conjoint 
rib on the left is 2.2 cm.; that of the first right rib, 1.3 cm. (Plate 
III.) 
The anomaly just described is rare in the human species. It 
has received the name of ‘ bicipital rib.’ It was first described 
by M. Hunauld,1 and was given considerable attention by Sir 
William Turner.2 The anomaly occurs invariably at the apex of 
the thorax (Turner), and consists mostly of a union of a cervical 
rib with the first thoracic.3 The anatomical peculiarity, accord- 
ing to Sir William Turner,4 “is not due to a bifurcation of the 
shaft of a single rib at its vertebral end into two heads, but to the 
fusion of what ought to have been the shafts of two distinct ribs 
into a common body.” The significance of the anomaly, when 
due to a union of a cervical with the first thoracic rib, must be 
about the same as that of a free cervical rib, the causes of which 
are not yet fully established. 
Supernumerary ribs occur both in man and in lower animals, 
and signify in all probability a recurrence of lower forms. Cuvier 
found supernumerary ribs in the bison ; Turner says the con- 
dition is quite common in the Cetaceae ; and I have been told by 
naturalists of examples of this kind in other mammals. Dr. F. 
Boas informs me that he found supernumerary ribs and vertebrae 
1 Memoires de I’Academic Royale de Paris, 1740, p. 525. 
2 Journal of Anatomy and Physiology, IV, November, iB6g ; V, May, 1871 ; XVII, April, 
1883, pp. 384-400. 
3R. Knox: London Medical Gazette, November 3 and 10, 1843. 
4 Journal of Anatomy and Physiology, XVII, p. 387. i 899-] 
Hrdlicka, An Anomalous Skeleton from Mexico. 
95 
in quite a high percentage of human skeletons from northwest 
Vancouver Island,1 and references to such phenomena are found 
in medical literature. In the majority of cases, the supernumerary 
ribs are cervical.2 Single supernumerary ribs are not so infre- 
quent as the bicipital ribs, though I have lately seen in Professor 
Dwight’s collection in the Anatomical Museum of the Harvard 
Medical School, Boston, Mass., a specimen of bicipital rib, much 
like that here described.3 
The union of two ribs in the manner here observed, in what- 
■ever portion of the thorax it may occur, implies a deficient evolu- 
tion of one of the ribs concerned, and a fusion of the two bones 
along more or less of their course during the early stages of ossi- 
fication of the parts. If the supernumerary rib is so deficient, as 
it is in this case, it shows that its cause, be it a reversion or any 
thing else, was less complete in this than in other instances 
where a similar rib is free. 
Dorsal arc of longest right rib * 30.3 cm 
Antero-posterior diameter between extremities of the bone . 20.5 cm 
Greatest height of ventral curve 7.5 cm 
Dorsal arc of longest left rib, 30.0 cm 
Antero-posterior diameter of longest left rib 20.2 cm 
Greatest height of ventral curve 7.5 cm 
Measurements of the Normal Ribs. 
The left ribs average about 6 mm, shorter than the correspond- 
ing right ones. 
Sternum. 
The sternum is 13.4 cm. high, and its maximum width is 5.4 cm. 
The whole bone is ossified,4 the original separations being marked 
by slight bony ridges. The lowest segment is perforated by two 
large foramina, the upper round, the lower oval. The left border 
of the sternum appears less developed in its upper third than the 
right, and is shorter, giving the bone a certain degree of curvature 
to the left. (Fig. 7.) 
1 These specimens are in the Field Columbian Museum, in Chicago, and have not been 
described. 
2 For further literature on the subject, see end of the paper. 
3 Since the above was written, I brought from Mexico (State of Jalisco) another bicipital 
rib ; and 1 also found in Professor Huntington’s anatomical collection, at the New York Col- 
lege of Physicians and Surgeons, a rib which represents an ancient fusion of the anterior 
portions of two bones, and has two articular facets anteriorly. (Plate 11, Fig. 2.) 
4 Complete ossification of the sternum, except in very advanced age, is decidedly an ex 
■ception among the Indians, in whom 1 generally find the manubrium detached. 96 
Bulletin American Museum of Natural History. 
[Vol. XII,. 
There are 7 articular facets for the ribs on the right side, and 
6 on the left; the first facet on the left 
occupying the place opposite and nearly 
between the right first and second. This 
form of the sternum shows that the anom- 
aly of the ribs originated early in the 
embryonic life of the individual. The 
blending of the first pair of ribs may be of 
a later though still foetal origin, and is 
less significant. 
When reconstructed, the dorsal part of 
the spinal column of the skeleton shows a 
moderate lateral curvature, convex to the 
left, and due no doubt to compensation for 
the lowering of the left side of the thorax,, 
caused by the joined pair of ribs. 
UPPER EXTREMITIES. 
Clavicles. 
Eig. 7. 
Front View of Sternum (sss) 
The clavicles present nothing unusual. 
Their mean length is 12.2 cm., and the 
bones are rather slender. 
Scapulae. 
The bones are light, and their form approaches that most 
common in the whites. 
Total height (inferior angle to superior angle) 14.1 cm 
Inferior angle to middle of glenoid fossa 13.5 cm 
Maximum breadth (lower border of glenoid to maximum 
point on posterior border) 9.3 cm 
Depth of glenoid fossae 0.4 cm 
Maximum depth of subscapular fossae 1.8 cm 
Maximum point of width on vertebral border to end of 
acromion _ 12.8 cm 
Maximum point of width on vertebral border to inferior angle, 10.45 cm 
™, , 1 • j 1 maximum breadth x 100/T5 \ „ 
total scapular index,1 —_ (Broca) 05.9 
total height 
1 This index is in the European 64.3 ; in the Bushmen, 66.2 ; in the Polynesian, 66.6 ; in the 
Chinese, 66.7; in the Peruvian, 66.5. Sir William Turner : Challenger Reports, XVI, p. 86, iS99-] 
Hrdlicka, An Anomalous Skeleton from Mexico. 
97 
Long Bones of the Arm 
These bones are of about medium size, and of normal shape. 
Both ulnae are lost. 
Length of right humerus 30.3 cm 
Length of left humerus 30.6 cm 
Mean antero-posterior diameter at middle 1.9 cm 
Mean lateral diameter at middle 1.4 cm 
Bicondyloid diameter 4.5 cm 
Natural perforation of right olecranon fossa Bx6 mm 
Natural perforation of left olecranon fossa 6x 4.5 mm 
Length of each radius (nothing special in aspect) 24.6 cm 
Humero-radial index 1 80.78 
Our subject, according to this scale, had his fore-arms, in pro- 
portion to his arms, even longer than the Negro, and is surpassed 
in this respect only by the Andamanese and by the Chimpanzee 
and the Orang. This index has full value with the subject 
in question, as all the bones of his upper extremities are entirely 
normal. But few of the.bones of the hand are present. They 
are rather slender, small in size, and show nothing unusual. 
The ossa innominata are normal, of medium strength. The 
whole pelvis is symmetrical, but unusually small. 
Pelvis. 
Maximum height of ossa innominata 18.7 cm 
Maximum breadth of ossa innominata.. 13.1 cm 
Maximum lateral diameter of pelvis (between external iliac 
crests) 25.5 cm 
Pelvic index 2 • 136.3 
Multiplying the width of the pelvis by 100, and dividing the 
product by the height of theossainnominata, gives the pelvic index. 
As seen by the table above, this index in the specimen in question 
is exceeded by that of a European woman only. The proportion 
of pelvic breadth to pelvic height has no bearing on the spacious- 
ness of the basin, which, as seen from the absolute values, is 
below the medium. The distance from the anterior and superior 
1 This index is in the Eskimo 71 ; in the European, 74 ; in the Australian, 77 ; in the Negro, 
79 ; in the Andamanese, 81 ; in the Gorilla, 80; in the Chimpanzee, go ; in the Orang, 100. 
Quain : Anatomy, Osteology, p. 99. London, 1893. 
2 This index in a European woman reached 136.9. In 46 male Europeans, it averaged 126.6 ; 
in 17 male African Negroes, 121.3 ;in 20 anthropoids, 105.6. Topinard : Elements d’Anthro- 
pologic, p. 1049. 
[May, iBgg.~\ 98 
Bulletin American Museum of Natural History. 
[Vol. XII, 
part of the pubis to the tip of the first sacral spinous process is in 
this case 15.6 cm. 
Internally : superior strait 
Antero-posterior diameter 9.0 cm 
Maximum lateral diameter 11.5 cm 
Index of superior strait (showing a high standard) 78.2 
Oblique diameter of superior strait 11.4 cm 
Tip of sacrum to inferior lip of pubis 10.4 cm 
Greatest interior separation of tubera ischii 9.0 cm 
Diameter between ischiatic spines 7.6 cm 
Subpubic angle, measured by projection about 58° 
Obturator foramen, medium size, obliquely triangular. 
LOWER EXTREMITIES. 
The bones of the lower extremities of this skeleton are inferior 
in strength to similar bones of an average white person. The 
long bones of the two limbs differ somewhat in length, the right 
femur and left tibia and fibula each being about 4 mm. longer 
than the same bones of the opposite side. 
Femora. 
The shape of the thigh-bones is rather peculiar. The neck is 
somewhat longer than in the average 
white. Below the smaller trochanter, 
the shaft is flattened (platymeric) an- 
tero-posteriorly. This flattening is not 
an anomaly, but a special ethnical char- 
acteristic, which I have found in many 
places in Mexico and elsewhere on this 
continent. (Fig. 8.) Below the upper 
third, the shaft of the femur becomes 
almost circular, and shows a moderate 
curvature forward.1 The linea aspera 
is not very pronounced. The condyles are normal. 
Fig. 8. Horizontal Section of the 
Right Femur 2 cm. below the 
Smaller Trochanter; a, Internal 
Border ; b, External Border ;c, An- 
terior Surface; d. Posterior Surface. 
Antero-posterior diameter of shaft 3.5 cm. below minor 
trochanter 2.0 cm 
Lateral diameter of shaft 3.5 cm. below minor trochanter.. 2.9 cm 
Average length of femur 40.9 cm 
1 The curvature of American femora often exceeds that of the femora of whites, and equals 
that of the Negro. i 899-1 
Hrdlicka, An Anomalous Skeleton from Mexico. 
99 
Maximum length of right femur 41.1 cm 
Maximum length of left femur 40.7 cm 
Antero-posterior diameter at centre 2.3 cm 
Lateral diameter at centre 2.25 cm 
Maximum breadth of condyles 6.7 cm 
Maximum antero-posterior diameter of condyles 5.6 cm 
Angle of neck 13°° 
Tible. 
These bones present at least two interesting characteristics : 
they are to a certain degree platycnemic ; and their heads, and 
the planes of the articular surfaces of the knees, are much more 
inclined backward than is usual. The shape of the tibiae, in 
transverse section at or above the middle, is quadrangular. The 
platycnemic condition of the tibiae is not especially significant. 
We find this characteristic distributed over immense areas of this 
continent, and in types of people differing physically to a con- 
siderable extent. Flat tibiae abound in Mexico, in our own 
southwest among the pueblos and the cliff-dwellers, in the great 
Mississippi basin among the mound-builders, as well as farther 
east to Florida, and farther west and north to British Columbia. 
I have measured flattened tibiae from Peru and Bolivia ; and as 
the range of anthropological material increases, this characteris- 
tic, rare in white races, is found common to vast regions, and 
apparently over both Americas. 
The backward inclination of the heads of the tibiae in this 
skeleton is a very marked characteristic, one much less frequent 
than the flattening of tibiae, and equally as interesting. I present 
two drawings of the upper part of one of the bones in question. 
These drawings demonstrate the inclination of the heads and 
the articular surfaces to the axis of the shaft. The inclinations 
are considerable, and involve the facets. (Figs. 9, 10.) 
The significance of this structural peculiarity is not clear. It 
is not certain that such an inclination of the head, and even of 
the articular facets, would necessarily affect the straightness of 
the limbs, and cause an inclination of the knees forward ; for a 
little overgrowth of the posterior parts of the femoral condyles 
could easily produce the proper compensation for such an inclina- 
tion. Such compensation would be detected only with consid- 
erable difficulty, due to the form of the femoral condyles, and I Bidletin American Museum of Natural History. 
[Vol. XII, 
am not positive whether it exists in this case. When the femur 
and tibia of one side are applied together, they can be adjusted 
in a straight line, without showing any unnatural position of the 
articular surfaces. 
Inclination of the head and of the articular facets of the tibia 
may be influenced by an habitual squatting position. Lighter 
grades of inclinations of the head of the tibia to the shaft are 
Fig. 9. Inner Side of Tibia 
Fig. 10. Outer Side of Tibia (&%) 
occasionally seen in all peoples ; but so high a degree as the 
tibiae of this skeleton present is very rare, and especially so in the 
white race. I have seen similar inclinations of the facets, and 
especially of the head of the tibia, in Apes, particularly in the two 
adult Gorillas preserved in Professor Huntington’s Anatomical 
Museum in the New York College of Physicians and Surgeons. 
The meaning and import of this structural peculiarity, I believe, 
cannot be definitely solved at present, but must be relegated to i 899-] 
Hrdlicka, An Anomalous Skeleton from Mexico. 
further specific studies. It is less rare in Americans than in many- 
other races of people. I have seen several grades of it in tibiae 
from different parts of this continent, in one belonging to the 
ancient Utah people, for instance ; and I found it quite common 
among our Mexican tribe, the Huicholes (Jalisco).1 
Average length of tibiae 35-45 cm 
Length of right tibia 35.3 cm 
Length of left tibia 35.6 cm 
Mean antero-posterior diameter at middle 2.8 cm 
Mean antero-posterior diameter at nutritive foramen 2.95 cm 
Mean lateral diameter at middle (the right bone is slightly 
thicker) 1.65 cm 
Mean lateral diameter at nutritive foramen 2.0 cm 
Index2 at middle 58.9 
Platycnemic index at nutritive foramen 3 67.8 
Femoro-tibial index of this skeleton 4 86.7 
Thus it is seen that our subject is as remarkable for the great 
length of his tibiae compared to his femora, as for similar relations 
of the bones of his fore-arms and arms. 
Fibulae. 
Their form is similar to that of whites. 
Length of right fibula 34.4 cm 
Length of left fibula 34.8 cm 
Proportion of lower limb (femur -(- tibia) to upper 
(humerus -(- radius) as 138.7 to 100.0 
Right Patella. 
Maximum height 4.4 cm 
Maximum breadth 4.6 cm 
Maximum thickness 2.15 cm 
1 See on this subject Collignon, Rev. d’Anthrop., 1880, v. IX; A. Thomson, J. of Ana. 
& Phys., London, XXIII, p. 616 ; Fraipont, Arch, de Biol., Gand, 1887, VII, f. 11l ; also 
Rev. d’Anthrop., jme serie, t. 111, p. 145. 
2 This index averages 71.1 in the white male, and 71.9 in the white female. 
3 This index was in 48 African Negroes (Topinard) 71,0. In Americans (Jeffries Wyman, 
Washington Matthews, and others), it ranges from 40 to 70; and I found it to be in a male 
adult Gorilla, 6x.8 ; in a female adult Gorilla, 65.6; in an adult Orang, 73.9 ; in a young 
Orang, 82.7. 
4 This index in 22 tall European males was 81.1 ; in 22 short European males, 79.7; in 5 
Chinese males, 80.2 ; in an Eskimo, 78.7; in 5 Polynesians, 82.2 ; in 3 Australians, 82.1 ; in 4 
Blacks of India, 82.8 ; in 32 African Negroes, 82.5 ; in 8 New Caledonians, 83.1 ; in 2 Tasmani- 
ans, 83.6; in 5 male South Americans, 84.1. This index is somewhat higher in the female of 
most races. In 2 female Bushmen it was 85.8 ; in a female Arab, 86.3 ; in a female Negrito, 
09.0 ;in 6 female South Americans, 83.x. Topinard : Elements d’Anthropologic, p. 1045. 102 
Bulletin American Museum of Natural History. 
[Yol. XII, 
Right Calcaneum. 
Maximum length 7.4 cm 
Breadth of body (in middle) 3.3 cm 
Height of body “ “ 4.5 cm 
The small bones of the foot present nothing special. 
In conclusion, then, the skeleton just described possesses the 
following principal points of interest : a pair of supernumerary 
ribs with all the characteristics of regular ribs ; very high relative 
lengths of the bones of the fore-arm and of the leg, and of the sa- 
crum ; and the peculiar lower jaw. As secondary points of inter- 
est, may be enumerated the small cranial capacity, the blending 
of the first left pair of ribs with consequent deformity of the 
spinal column and of the sternum, the pterygospinous foramen 
(ossification of pterygospinous ligament), the sternal foramina, 
the perforation of the olecranon fossae of the humeri, the six 
segments of the sacrum, the platymery of the femur, a certain 
degree of platycnemia, and marked inclination backward of the 
head and of the articular facets of the tibiae. 
In measurements, the skull is highly brachycephalic with but 
comparatively moderate compression of the occiput : uncom- 
pressed, the head could not possibly have been dolichocephalic. 
The face is mesoseme, or of medium breadth in relation to its 
height. The orbits are high, or megaseme. The nasal aperture 
is lower and broader than in the whites, and platyrrhinic. The 
posterior nares are of lesser height than breadth. The angle 
of the lower jaw is low. There is more prognathism in appear- 
ance than is shown by measure ; it is confined to the upper 
alveolar process. The humeri show no unusual torsion. The 
femoral angle is within the limits of the ordinary. The propor- 
tion of lower to upper limbs is as 138.7 to 100. The pelvis is 
rounder than in the European, but considerably smaller. The 
feet and hands were slender. The subject was right-handed, or, 
more properly, right-sided, as is indicated by the greater strength 
of the bones of the extremities on the right side. 
So much for the more interesting anatomical characteristics of 
this skeleton. The next question is, What is the anthropological 
significance of all the peculiarities observed in this one body ? 
It is clear that a skeleton devoid of pathological abnormities— 
which is fully adult and not too aged,’and which presents such x 899-] 
Hrdlicka, An Anomalous Skeleton from Mexico. 
103 
characteristics as this shows—is an exceptional, if not unique 
occurrence. If the skeleton represents a race of people, it is of 
the highest importance to knowr more about this race and its 
place in the rise of mankind. It is safe to say that this is the 
skeleton of a being zoologically on a lower scale than is the 
average white man of to-day, and much inferior even to the known 
old or present inhabitants of the Valley and State of Mexico. 
Many of the characteristics of this adobe skeleton approach those 
of the skeletons of the anthropoids. 
The Museum has in its possession but few whole skeletons 
from the same locality, and none of these show any marked ab- 
normality. On the other hand, only a few of the peculiarities 
observed in this specimen are such as usually occur otherwise 
than racially in a normal individual. It seems, however, that, 
having but one skeleton to consider, the question of individual or 
racial character of the abnormalities must remain an open one, 
pending further investigations on additional material from the 
same locality. 
To which of the Mexican ethnic groups do this skeleton and the 
skulls from the same region belong? For a satisfactory answer 
there is requisite somatological knowledge of the various groups 
of the inhabitants of that old and ethnologically highly important 
region, the Valley of Mexico, as well as a precise knowledge of 
the geological and archaeological conditions of the adobe deposits 
with their various layers. Of this fact we are certain, that from 
prehistoric time there have dwelt in the Valley of Mexico a 
number of more or less distinct peoples, and that most of the 
people who have been settled in that valley within the last twelve 
or fifteen hundred years belonged to a stock collectively termed 
‘ Nahuatl.’ The very last of the Nahuatl branches who gained 
supremacy in the valley were the Aztecs, whose progeny occupy 
to-day some of the regions around the City of Mexico. There 
can be no doubt that the skeleton described is ancient. Does it 
belong to the Aztec people, or does it date still farther back,— 
to some of the Aztec predecessors ? 
Little is known anatomically about the Aztecs. What we do 
know is mainly due to Hamy and Quatrefage of Paris. Sergi ex- 
amined a number of Aztec skulls ; and I had occasion to examine 
some, among which was that of a normal adult male, whose 104 
Bulletin American Museum of Natural History. 
[Vol. XII, 
ancestors were known. The characteristics of Sergi’s and my 
own specimens accord in the main with the observations of 
Hamy. The main features of these presumably Aztec skulls are, 
that not one of them has been found artificially deformed in any 
way, and that they are regularly dolichocephalic. In both these 
characteristics, this skull, with a number of its companions, differs 
from Aztec skulls. A number of the male specimens are de- 
formed ; and their lowest indices, even in the totally undeformed 
crania, are but mesocephalic. These crania have belonged to 
some much shorter-headed people than were the Aztecs, possibly 
to a different race of people. This race lived contemporaneously 
with, or but little anterior to, this last branch of the Nahuatl 
family, for the short skulls are found together with the long ones. 
Previous to the Aztecs, the Valley of Mexico is said to have 
been occupied by the so-called Chichimecs, of whom ethnically 
and physically we know little. Still earlier the region was peo- 
pled by the so-called Toltec nation. Of the pre-Toltec inhabi- 
tants of the valley, every thing is uncertain. 
The Toltecs have left great monuments, and no doubt also a 
large number of osseous remains, for which, as yet, no systematic 
search has been made. Our knowledge of them is due either to 
archaeological excavation or to accident. What material has 
been secured is seldom properly identified, and is so scattered as 
to be inaccessible to a single student. Nevertheless, the refer- 
ences in anthropological literature to the skulls of these people 
all agree in the main particulars. The most extensive of these 
references is to be found in Morton’s ‘ Crania Americana.’ Mor- 
ton, it is well known, attributed to the Toltecan people a great 
extent and high importance. Another mention of Toltec skulls 
is to be found in Quatrefage and Hamy’s ‘ Crania Ethnica ; ’ and 
still another, though not direct, is in the ‘ Catalog de la Collec- 
tion de Anthropologia del Museo Nacional,’ por Alfonzo L. 
Herrera y Ricardo E. Cicero. 
In all the above descriptions the Toltecan skulls are repre- 
sented as more or less brachycephalic, and often deformed. 
These are likewise the prominent characteristics of one portion 
of the St. Simon skulls, including the cranium of the skeleton de- 
scribed. The six more or less deformed male skulls of the col- 
lection show cephalic indices of from 86.0 to 93.4 ; three male 1899] 
Hrdlicka, An Anomlous Skeleton from Mexico. 
105 
undeformed skulls reach indices of from 77.4 to 81.7 ; and the 
average cephalic index of the five undeformed female skulls is 
81.4. The illustrations which Morton gives of his Toltecs agree 
also with the shape and general aspects of some of the skulls 
from St. Simon. For comparison three views of male skulls from 
this place are given in Plates IV and V, the middle one being 
that of the above-described skeleton. 
Morton and Meigs considered as Toltecs all American aborigi- 
nes who attained a certain degree of civilization, and included 
within this group the mound-builders, the cliff-dwellers, and 
others. Outside of Toltecs there was only one more group of 
Americans, and those were the Barbarians, which included most 
of the North and South American Indians. Since Morton and 
Meigs, however, the term ‘ Toltec ’ has become gradually re- 
stricted ; most historians and most recent authors understand by 
it the people who occupied the Valley of Mexico before the 
Chichimecs, Acolhuas, and Aztecs,—people who may also have 
belonged to the Nahuatl stock, and who disappeared before the 
later Nahuatl invasions, leaving behind them signs of high 
culture, and possibly a part of this culture itself. 
Under these conditions it would be very difficult to define the 
proper ethnic nature of the specimen. I cannot term it the 
skeleton of a Toltec, so long as the vagueness of this term con- 
tinues. The possibility that it is Aztec cannot be excluded, but 
then it would be greatly exceptional. Nothing more definite 
can be established until the Mexican Valley adobe deposits have 
been thoroughly explored and studied, and until we possess large 
collections of ‘ Toltec ’ and adobe skulls and skeletons. 
However, the uncertainty as to the particular race to which the 
subject belonged is really of secondary importance, and, it is 
hoped, will not detract from the interest of the features of the 
skeleton which have been made the subject of this paper. In 
conclusion I may remark that human osseous remains from vari- 
ous parts of Mexico are prolific in interest, and particularly in 
zoologically inferior characters, and that they deserve pre-emi- 
nently the thorough attention of anthropologists. 106 
Bulletin American Museum of Natural History. 
[Vol. XII, 
FURTHER LITERATURE ON BICIPITAL, CERVICAL, AND SUPER- 
NUMERARY RIBS. 
Aeby, C. Seltene Rippenanomalie des Menschen. Arch. f. Anat. Physiol, 
u. wissensch. Med.. Leipz., 1868, 68-71, x pi. 
Aron, E. Zur Casuistik der Halsrippen. Berl. klin. Wochenschrift, 1892, 
No. 33, 826-828. 
Bernhardt. Berl. klin. Wochenschrift, 1895, XXXII, 4. 
Blandin. (Articulation centre nature existant a la partie moyenne d’une 
premiere cote d’adulte.) Bull. Soc. Anat. ae Par., 1828, 2 ed. 1845, 111, 38. 
Clark, H. E. Notes on a case of cervical ribs. Glasgoiv M. J., 1874 (5) 
s., VI, 361-363. 
Coues, E. Free cervical ribs in the human subject. Science, Cambridge, 
1884, 111, 61. 
Dwight, T. Two cases of cerv. ribs. f. Anat. Sf Phys., Lond., XXI, 
P- 539- 
Dymock, A. On the occurrence of supernumerary cervical ribs in the human 
body. Edinb. M. & S.J., 1833, XI, 304-307. 
Ehrich, E. Zur klin. Symptomatol. der Halsrippen. Beitr. z. kliti. Chir., 
1895, XIV, 1, p. 199. 
Ekhorn, G. Skelett med tretton par refben (A skeleton with 13 pairs of 
ribs). * Upsala Lakaref. Forh., 1884, XIX, 231-235. 
Fere, C. Anomalie d’une cote. Bull. Soc. Anat. de Par., 1880, LV, 290. 
Also : Progres med. Par., rBBo, VIII, 1059. 
Foucher. (Une cote surnumeraire.) Bull. Soc. Anat. de Par., 1856, 
XXXI, 69. 
Gillette. (Deux cotes surnumeraires au sommet du thorax.) Bull. Soc. 
Anat. de Par., 1869, XLIV, 72. 
’ Gruber, W. Vortauschung einer Fractur derersten Rippe durch eine kurze 
supernumerare Rippe. Arch. f. path. Anat., etc., Berl , 1865, XXXII, 
108-110. 
Halsrippe bei Canis familiaris. Arch, f. Anat. Physiol, u. wissensch. 
Med., Leipz., 1867, 542-546, 1 pi. 
Gelenkige Verbindung der ersten mit der zweiten Rippe an deren 
Korpern. Arch. f. path. Anat., etc., Berk, 1875, LXV, 11, 1 pi. 
Ueber einen Fall von unvollkommen gebildeter erster Brustrippe. 
Ibid., 1876, LXVII, 344-352, x pi. 
Verwachsung zweier Rippen durch eine congenitale Knochenplatte 
zwischen deren Halsen. Ibid., 1877, LXX, 139. 
Ein Beispiel congenitaler Verwachsung der ersten und zweiten Rippe 
der linken Seite. Ibid., 1879, LXXVIII,- 97, 
Ein Beispiel einer abnorm verbreiterten und tief gefurchten Rippe 
mit gabliger Spaltung am vorderen Ende und inselformiger Spaltung am Korper. 
Ibid., 98-100, 1 pi. 
Congenitale Verwachsung der ersten mit der zweiten Brustrippe der 
rechten Seite und congenitale Verkummerung der ersten Brustrippe der linken 
Seite an einem und demselben Skelet. Ibid., 1880, LXXX, 82. 
Herv6, G. Anomalie de la premiere cote. Bull. Soc. d’Anthrop. de Par., 
1883, 3. s., VI, 194-196. 
Hunaui.D. Sur le nombre des cotes moindre ou plus grand qu’ a I’ordinaire. 
Hist. Acad. ray. d. Sc. (de Paris), 1740, Amst., 1744, Mem., 534-539. 
Huntemuller. Ueber Halsrippen und anomale Rippengelenke. Ztschr. 
f. rat. Med., Leipz. u. Ileidelb., 1867, 3 R., XXIX, 149-157, 1 pi. 
Jewett, C. Costa cervicalis. Ann. Anat. & Surg. Soc., Brooklyn, N. Y., 
1878-79, I, 101. 
Lane, A. Cervical and bicipital ribs in man. Guy's Hasp. Rep., Lond., 
1883-84, XLII, 109-133. 1899-] 
Hrdlicka, An Anomalous Skeleton from Mexico. 
107 
Lane, W. A., and White, W. H. Cervical rib. Tr. Clin. Soc., Lond 
1885, XVIII, 334. 
Leboucq, H. De quelques anomalies des cotes chez I'homme ; cotes cer- 
vicales et premiere cote thoracique rudimentaire. Ann. Soc. mid. de Gand, 
1885, LXIV, 34-44, 2 pi. 
Macdonnell, R. L. Note on a case of bicipital rib. y. Anal. & Physiol., 
Lond., 1885-86, XX, 405. 
Pascal. Cote cervicale chez I’homme. Rec. de mint, de mid. mil.. Par., 
1848, 2 s., IV, 175-177. 
Pepper, W. Supernumerary rib. Am. y. M. Sc., Phila., 1867, LIV, 148. 
Also: Proc. Path. Soc., Phila. (1866-70), 1871, 111, 32. 
Prioleau. Une cote bifide et dans sa partie osseuse et dans sa partie carti- 
lagineuse. Bull. Soc. d’Anat. et Physiol, de Bordeaux, 1883, IV, 11-13. 
Pulawski, A. Defects of ossification of some ribs a frequent cause of 
abnormalities of structure. Gaz. lek., Warszawa, 1888, 2. s., VIII, 237-240. 
Reid, R. W. A female subject showing cervical ribs. Proc. Anat. Soc. 
Gr. Brit. Sf Ireland, Lond., 1889-go, p. iii. 
Romiti, G. Varieta costali : coste cervicale. Gior. internaz. d. sc. med. 
Napoli, 1880, 11, 674-678. 
Scott, J. H. Note of a case of articulation between two ribs. y. Anat. 
& Physiol., Lond., 1878-79, XIII, 577. 
Note on a specimen of bicipital rib. Ibid., 1883-84, XVIII, 339. 
Srb, I. Ueber Missbildungen der ersten Rippe. Med. yahrb., Wien, 1862, 
IV, 75-82. 
Stieda, L. Ueber Halsrippen. Arch. f. path. Anat., etc.. Herb, 1866, 
XXXVI, 425-434, 1 pi. 
Streets, T. H. Supernumerary ribs. Am. y. M. Sc., Phila., 1872, n. s. 
LXIV, 13 x. 
Struthers, J. On variations of the vertebrae and ribs in man. y. Anat. 
6° Physiol., Lond., 1874-75- IX, 17—96- 
Tenchini, L. Sulle varieta numeriche vertebro-costali nell’ uomo. Ateneo 
med. parmense, Parma, 1889, 111, 179-2xo. 
TILLMANN. Die klin. Bedeutung der Halsrippen. Deutsche Zeitschrift f. 
Chir., 1895, XLI, 4-5, 330. 
Wallace, D. On cervical ribs. Edinbg. y., Febr., 1892, 706-710. 
Willshihe. Supernumerary first rib. Lancet, Lond., iB6O, 11, 633. 
Zaaijer, T. Anomalie de la premiere et de la seconde cote. Arch, neerl. 
d. sc. exac/es, etc., La Haye, 1872, VII, 456-459, 1 pi. Bulletin A. M. N. H. 
Vol. XII, Plate I. 
Front and Side Views of Skull, No. s95*3. Bulletin A. M. N. H. 
Vol. XII, Plate 11. 
Fig. i. Lateral View of Lower Jaw,‘No. t&V 
b 
Fig. 2. a, Bicipital Rib (fragmentary) from an Ancient Burial-Place in the 
State of Jalisco, Mexico ; A Broad Rib with two Facets, formed by 
Union of First and Second Ribs ; Provenience Unknown. (Anat. Coll., 
Coll. Phys. and Surg.) 
a Voi.. XII, Plate 111.- 
Ventral and Dorsal Views of Ribs and Spinal Column, No. 
Bulletin A. M. N, H. Vol. XII, Plate IV. 
Lateral View of* Three Brachycephalic Skulls from the Adobe Deposits of St. Simon, Valley of Mexico. 
Bulletin A. M. N. H. Vol. XII, Plate V, 
Front View of Three Brachycephalic Skulls from the Adobe Deposits of St. Simon, Valley of Mexico. 
Bulletin A. M. N. H. Übe TKnichetbocfcet jprcss, flew Sock