MAMMALIA 103 



of either jaw, and they are replaced by others which grow from 

 behind and gradually push out their predecessors as these get 

 worn away. It is scarcely necessary to remark that in the vast 

 majority of mammals teeth are succeeded by others which grow 

 up vertically below them. The skull of an adult elephant is of 

 remarkable form, and the cranium is much larger than the brain 



Fig. 71. African Elephant (Loxodon Africaiius}. (From an instantaneous photograph 



which it contains, owing to the excessive development in its 

 roof of air-chambers separated by complex bony plates. It 

 may lastly be noted that the thick skin is but sparsely covered 

 with hairs, and that the mammary glands are situated much as 

 in a cow. The food consists exclusively of vegetable matter. 



Elephants are now represented by only two genera, one the 

 Indian form (Euelephas Indicus), found also in Ceylon, Borneo, 

 and Sumatra, while the other (Loxodon Africanus) is limited to 

 Africa south of the Sahara (fig. 71). 



Order 9. CONIES (Hyracoidea) 



This small order includes only certain little creatures about the 

 size of a rabbit, which inhabit the deserts of Africa and Syria. 

 The general resemblance to a rabbit is seen chiefly in the cleft 

 upper lip, and the presence of two long upper incisors which grow 

 continuously, while canine teeth are entirely absent. In the 



