ORDERS OF MAMMALIA. 



297 



A.. Perissodactyla, or Odd-toed Ungulates, in which the 

 toes are odd in number either one or three* If horns 

 are present, they are not in pairs. 



J3. Artiodactyla, or Even-toed Ungulates, in which the 

 toes are even in number either two or four / and, if 

 horns are present, they are in pairs. 



The living Perissodactyle Ungulates are the Rhinoceroses, 

 the Tapirs, and the Horse and its allies. The Rhinoceroses 

 are extremely large and bulky brutes, having a very thick and 

 nearly hairless skin, usually thrown into deep folds. The 

 feet (Fig. 147, D) are furnished with three toes each, all en- 



FIG. 147. Ungulata. A, Perissodactyle foot of Zebra. B, Artiodactyle foot of Llama. 

 C, Artiodactyle foot of Antelope. D, Perissodactyle foot of Ehinoceros. 



cased in hoofs. The nose is furnished with one or two horns, 

 composed of longitudinal fibres compacted together, and not 

 having any central core of bone. When there is only one 

 horn, it is, of course, unsymmetrical ; and, when there are two, 

 these are not paired, but one is always placed behind the other 

 in the middle line of the head, and the hinder one is much the 

 shorter. The various species of Rhinoceros are found in 

 India, Java, Sumatra, and Africa, inhabiting marshy places 

 and feeding chiefly on the foliage of trees. The Tapirs have 

 four toes to each of the fore-legs, but only three toes on the 

 hind-legs, so that they are properly odd-toed. The nose forms 

 a short, movable proboscis, used in stripping- off the leaves of 

 trees. They are large, clumsy animals, which inhabit South 



* The fore-feet of the Tapirs are even-toed, but the hind-feet are perissodactyle. 



