600 ZOOLOGY. 



the rhinoceros among the Ungulates, the members of this 

 small order are in general characterized by having long,, 

 curved incisors ; and by feet provided with pads as in Ro- 

 dents and Carnivora, the toes being encased in hoofs (four in 

 front and three behind). The Hyrax, a little gregarious- 

 animal living in holes among rocks, of which there are two 

 or three species known, one South African, and another in 

 the Holy Land and Arabia, thought to be the coney referred 

 to in the Bible, is the only genus. 



Order 9. Toxodontia. Of this group, of which no spe- 

 cies are now living, the types are Toxodon and Nesodon* 

 They are placed by many authors among the odd-toed Ungu* 

 lates, not far from the tapirs. Their incisors were f or . 

 Toxodon in its skull bore some resemblance to the Sirenians, 

 and in the teeth were in certain respects like the Edentates. 

 The species lived in South America during the early Tertiary 

 Period. 



Order 10. Ungulata. The larger proportion of mammals 

 belong to this interesting order, which comprises nearly all 

 those species of mammals useful to man, such as the ox, 

 camel, pig, deer, and horse. They are, in general, charac- 

 terized by walking, so to speak, on their toes, each toe being 

 at the end encased in a horny hoof ; not more than four toes 

 being completely developed on a foot. The teeth are usually 

 well developed, with six incisors in each jaw, but these are 

 often, especially in the upper jaw less in number or entirely 

 absent, as in the sheep, deer, and ox. The collar-bone is 

 absent. The brain still remains small compared with the 

 bulk of the skull, and the intestinal canal is of unusual 

 length compared with that of animals of the previous orders. 



The Ungulates have been divided by Owen into two sub- 

 orders, according to the odd number of toes (Perisso- 

 dactyla) or even number (Artiodactyla). In the Perisso- 

 dactyles there may be three toes on each foot, as in the rhi- 

 noceros, or one, as in the horse ; while in the Artiodactyles 

 there may be four toes (Hippopotamus), or two, as in the 

 giraffe, or two functional and two rudimental, as in the ox 

 and deer, i. e., most Ruminants. The more generalized ex- 

 isting form of Ungulates is the tapir ; the most specialized 



