SKELETON OF CARNIVORA. 



487 



334 



Bones of hiud-foot of 

 Clievrotaiu (Tragulus). 



XCVI-. 



Chevrotains for the support of the slender metatarsal of the toe 

 answering to the second of pentadactyle feet. The corresponding 

 metatarsal, fig. 334, c, of the fifth or outermost toe, ib. b, articu- 

 lates with the cuboid, 9. In Moschus aquaticus, the second and 

 fifth metatarsals coexist with an almost complete 

 severance of the third and fourth, which, in a 

 state of confluence, represent the metatarsal seg- 

 ment in other Ruminants. The true Musk-deer 

 and most horned Ruminants have the distal ends 

 of the second and fifth metatarsals ossified, and 

 supporting the small digits terminated by the 

 'spurious hoofs,' fig. 193, ii, v: in the Giraffe 

 and Camel tribe these are wholly absent, as are 

 their homotypes in the fore-foot. The digital 

 phalanges of the hind-foot, fig. 330, B, ii, 12, 13, 

 h, closely correspond with those of the fore-foot. 



In all Uno'ulates the encasino- of the end of 

 the digit in a hoof is accompanied by a junction 

 of the radius and ulna such as to jDrevent recipro- 

 cal rotation of those bones on each other, and by 

 a joint with the humerus restricting the movements of the anti- 

 brachium to flexion and extension in one plane. The expansions 

 of the humerus for attachment of pronator and supinator muscles 

 are uncalled for ; while the proximal processes gi^^ng leverage to 

 the permitted motors of the limb may project in a degree which 

 would impede its more varied and freer motions. The length of 

 the blade bone and of muscles arising from it is increased at the 

 expense of their breadth ; the acromion is stunted, and clavicles 

 are absent. The concomitant modifications of the skull and jaws 

 in relation to masticating vegetable food are best exemplified in 

 the Ruminant Ungulates, and have been specified at p. 471. 



§ 189. Skeleton of Carnivora. — In the Unguiculate Gyren- 

 cephala the whole frame is modified, in degrees corresponding 

 with the perfection of the claws as prehensile weapons, for 

 mastery and destruction of other animals. The mandible, fig. 

 341, 32, is short and strong, it is articulated by a close-fitting 

 joint to the skull almost restricting its movements to one plane, 

 as in opening and closing the mouth, for biting, and for dividing, 

 not pounding the food. The coronoid process giving insertion to 

 the temporal muscles is broad and high; the fossae from which 

 they rise are large and deep, and augmented by peripheral ridges 

 of bone. The zygomatic arch spans across the muscle, bending 

 outward to give space for its passage, and arching upward for the 



