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breadth constitute a kind of osseous case, en- 
closing a considerable portion of the abdominal 
cavity, and calculated to give origin to muscles 
of power proportioned to its ponderous con- 
tents. 
In the Hyrax, dissected by Pallas, there 
were twenty-two ribs on the left side and only 
twenty-one on the right: of these seven were 
true ribs, six false attached to the sternum by 
the intervention of costal cartilages, and the 
rest merely imbedded in the muscles of the 
flanks. e sternum consisted of six pieces, 
of which the last or ensiform was further pro- 
longed by a spathulate cartilage. 
In the Tapir the ribs are twenty in number 
on each side, whilst there are but four lumbar 
vertebre. The Elephant, likewise, has twenty 
ses of ribs and only three lumbar vertebre. 
e Rhinoceros has nineteen pairs of ribs, and 
the Hog only fourteen. 
The sternum is of considerable length and 
compressed laterally. In many genera, more- 
over, it is prolonged in front to a considerable 
distance, in order to allow more ample space 
for the attachment of muscles. 
Anterior extremities.— The limbs of the 
Pachydermata are necessarily constructed more 
with a view to ensure strength adequate to sus- 
tain their ponderous bulk than to permit of 
agile and active movements. The smaller 
enera, indeed, such as the Snide, have their 
nes so arranged as to permit of considerable 
fleetness in running, but in the more colossal 
genera the condition of the extremities secures 
support at the expense of speed, and flexibility 
is sacrificed to solidity and firmness. 
Scapula.—The shoulder-blade of the Ele- 
phant, independently of its size, might be 
distinguished from that of any other living 
animal by the following circumstances. When 
in situ, its posterior side, which is deeply con- 
cave, is by far the shortest of the three, while 
the anterior and spinal coste are of nearly 
equal length. In consequence of the preceding 
circumstance this scapula is broader in propor- 
tion to its length than that of any other 
large quadruped, and, moreover, the spine of 
this bone, besides its acromial process, has 
towards its middle a broad sickle-shaped pro- 
jection, looking backwards and spreading over 
PACHYDERMATA. 
the infra-spinatus muscle. In all other Pachy- 
dermata the shape of the scapula is that of a 
elongated triangle, with the angles of the base 
much rounded off and the spine very short in 
proportion to the extent of the dorsum; never= 
theless, in the Rhinoceros there is a falciform 
aged projecting from the spine somethin 
ike that of the Elephant, and both in th 
Hippopotamus and the Tapir rudiments of 
coracoid process. The scapula of the Tapir (fig 
475) is also remarkable for a deep and almo: 
circular notch between the rudimentary 
mion and its anterior costa. 
Clavicle.—None of the Pachydermata I 
the slightest rudiment of a clavicle, an ; 
ment which permits the anterior shoulders — 
be closely approximated beneath the thora 
and thus temas nearer to the centre of gravit 
Humerus.—The humerus is in all cases she 
massive, and remarkable for the size and stren 
of the ridges and prominences for the orig 
and insertion of the muscles connected with 
The head of the bone which articulates 
the scapula is very flat, and although lar 
forms but a very small proportion of its seapu 
extremity, the rest being made up of enormous’ 
protuberances, to which are affixed the mus 
of the shoulder. ( Figs. 474 and 475.) 
The lower articulating surface is a sim} 
pulley, articulating with the conjoined hi 
of the radius and ulna, so as to admit of flex 
and extension only, no movements of pronal 
or supination being here admissible. a 
The humerus of the ar ee (fig. 464 
distinguishable from that of all other quadrup 
by the prodigious extent of the external cond 
which extends upwards nearly one-third of 
length of the bone, where it terminates abru 
ae to give a square form to this part 
ne. 
Radius and ulna.—As the position 
fore-arm in the Pachydermata is perma 
that of pronation, no arrangement has 
made in any instance to articulate the f 
with the ulna by means of a moveable joi 
certain degree of elasticity (the result of 
mentous connection) being all the m 
allowed even where the separation between 
two bones is most complete. Sometimes, 
deed, as in the case of the Hippopotamus 
