506 Vertehrata. 



pulps and are more curved tliau those of the female) ; the premolars are com- 

 pressed, the molars have broad tuberculate grinding surfaces. Here . belong the 

 European "Wild Hog [Sus Scro/a), the ancestor of the old race of the 

 North European Domestic Pig; most existing English breeds are 

 hybrids of the latter and of the Chinese pig, which was derived from one or more 

 species of Asiatic Wild Pigs, and difEers in several respects (in the skeleton) 

 from the old race and from the Eui-opean Wild Hog. 



(6) Among other Suidse the following may be noticed : the Peccaries 

 (Dicotyles), small foims, with a large skin gland dorsally ; the fifth hind toe is 

 wanting ; the canine in the upper jaw is directed downwards, but neither it nor 

 that of the lower jaw is of striking size ; South America. In the Babyrusa 

 of Celebes (Porous hahyrusa) the canines of the upper jaw are turned upwards 

 and much curved, in the male they are enormously elongated. The Wart-hog 

 (Phaeochcerus) is chiefly distinguished by the extraordinaiy development of the 

 last molar, this tooth is also the largest in Sus ; m. very old animals it is the only 

 persisting molar ; canines much like those of Sus ; South Africa. 



2. Hippopotami {Hippopotamidsfj are huge animals with thick limbs; 

 the second and fifth digits are very powerful ; the animals place all four toes on 

 the ground and the sole of the foot is large ; molars plicate and tuberculate ; 

 incisors and canines very powerful ; head very large, without a proboscis, with 

 very broad snout, sparsely covered with hairs : only two living species ; the best 

 known is the Hippopotamus {H. am/phihius), which is distributed over large tracts 

 in Africa ; another smaller species [Cheer opsis Kberiensis), which approaches the 

 Suidse in some respects, inhabits West Africa. 



3. There are also many extinct Non-ruminants, which are in some 

 points like the Pigs and Hippopotami, but in others differ considerably from 

 them. There are, for example, various forms with molars like those of the 

 Ruminants, whilst in other respects they stand fairly close to the Suidse ; others, 

 like the Anoplotherium of Eocene and Miocene times, with long neck and 

 long legs, offer a superficial resemblance to the Ruminants, but are distinguished 

 from them by the possession of a complete dentition (y^) > ^7 the well-developed 

 upper incisors ; and by the separation of the metatarsals. 



GrroTip 2. Kuminantia. 



Incisors are absent from the premaxillae (or the third is alone 

 developed) ; canine of the lower jaw usually (but not in the Camels) 

 like the incisors, so that there appear to be four of these in each 

 ramus. The molars, and to some extent the premolars also, have 

 each four curved longitudinal ridges, two external and two internal. 

 On all four limbs, the third and fourth metatarsals (or metacarpals) 

 are almost invariably fused, forming a single long bone (cannon 

 bone), whilst the second and fifth are incomplete or absent*; in the 

 Tragulidse alone are they complete. Digits two and five are small 

 or absent. For the structure of the hoof, see p. 470 and Fig. 382 E. 

 Ulna and fibula are poorly developed ; the lower end of the latter is 

 separate, and resembles a tarsal bone. Eami of the lower jaw 



* The upper ends of the second and fifth are, at least in the hind foot, fused with 

 the third and fourth respectively, but the rest, if present, remain as small separate 

 bones. 



