442 



ORDERS OF MAMMALIA. 



except the Elephants, but including also the extinct Mastodon 

 and Deinotherium. 



The order is characterised by the total absence of canine 

 teeth ; the molar teeth are few in number, large, and trans- 

 versely ridged or tuberculate ; incisors are always present, and 

 grow from persistent pulps, constituting long tusks (fig. 359). 



Fig- 359- Skull of the Indian Elephant (Elephas Indicus). /Tusk-like upper incisors ; 

 m Lower jaw, with grinding molars, but without incisors ; n Nostrils, placed at the ex- 

 tremity of the proboscis. 



In all the Elephants there are two of these tusk-like incisors in 

 the upper jaw, and the lower jaw is without incisor teeth. In 

 the Deinotherium this is reversed, there being two tusk-like 

 lower incisors and no upper incisors. In the Mastodons, the 

 incisors are usually developed in the upper jaw, and form tusks, 

 as in the Elephants ; but sometimes there are both upper^and 

 lower incisors, and both are tusk-like. The nose is prolonged 

 into a cylindrical trunk, movable in every direction, highly 

 sensitive, and terminating in a finger-like prehensile lobe (fig. 

 359). The nostrils are placed at the extremity of the proboscis. 

 The feet are furnished with five toes each, but these are only 

 partially indicated externally by the divisions of the hoof. The 

 feet are furnished with a thick pad of integument, forming the 



