444 UNGULATES. 



When taken young, peccaries are easily tamed, although it does not appear that 

 any attempts have been made to establish a domesticated breed. Large numbers 

 of them are destroyed by jaguars and pumas. 



Fossil remains of peccaries, some belonging to living and others 

 to extinct species, occur in the Pleistocene deposits of both North and 

 South America. In addition to these, certain extinct Pliocene and Miocene hog- 

 like animals seem to indicate the parent-stock from which both the peccaries and 

 the true pigs have been derived. Of these Chcerohyus, from North America, comes 

 closest to the peccaries, while the Old World Hyotherium, of which two upper 

 molar teeth are figured on p. 421, is more like the pigs. Listriodon is another 

 European type, in which the molars have a pair of transverse ridges instead of 

 four tubercles. Finally Chatropotamus, from the upper Eocene of England and 

 France, connects the type of molar tooth characteristic of the pigs with that of the 

 extinct anthracothere referred to on p. 421. 



The Hippopotami. 

 Family HlPPOPOTAMlD^:. 



Although the Greek term hippopotamus, and its English equivalent river- 

 horse, are etymologically decidedly objectionable ones to denote the animals we have 

 now to describe, yet the former at least is so firmly established in European 

 languages that it would be impossible to attempt to change it. The Dutch term 

 see-kuh, commonly translated sea-cow, but which we think might equally bear the 

 interpretation lake-cow, and a name used by the Arabs which means water-buffalo, 

 are far less objectionable ; but a title equivalent to river-swine, which is said to 

 have been conferred on these animals by the ancient Egyptians, is, from a zoological 

 standpoint, far and away the best of all. 



The common hippopotamus, together with a much smaller species from West 

 Africa, constitute a family by themselves, which is also the last group of the even- 

 toed Ungulates. Hippopotami are bulky animals, with round, barrel-like bodies of 

 great length, very short and thick legs, and enormous heads, in which the muzzle 

 is angular and greatly expanded transversely, and has no trace of the terminal ilisc 

 characteristic of the swine and peccaries. Indeed, the ugly head of a hippopotamus 

 appears as if it were too large and heavy for its owner, since the animal may fre- 

 quently be seen resting its ungainly muzzle on the ground, as though to relieve the 

 neck from the strain of its weight. The portion of the skull in front of the eyes 

 is very much longer than that behind them; and the sockets of the eyes (as 

 seen in our figure of the skeleton) are completely surrounded by a very prominent 

 bony ring, which has an almost tubular form. In the pigs, on the other hand, the 

 socket of the eye is open behind (compare the figure on p. 422). The prominence 

 of these sockets causes the relatively small eyes of the hippopotamus to project far 

 above the level of the forehead. The ears are small and rounded, and the slit-like 

 nostrils are placed rather close together on the highest point of the broad bristly 

 muzzle ; while both ears and nostrils alike can be completely closed at the will of 

 the animal. The neck is extremely short and powerful ; and the body is so deep, 



