290 AFRICAN GAME ANIMALS 



the corners of the muzzle are the elongated nostrils. The 

 eyes are small, pig-like, and mounted on the upper surface 

 of the head. Behind them, a short way, project the diminu- 

 tive rounded ears. The only parts of the body which show 

 a growth of hair are the tip of the short tail, the inside of 

 the ears, and the muzzle from the nostrils to the lips. 

 There are at the present time two living genera, both con- 

 fined to Africa — the gigantic river hippopotamus, Hippo- 

 potamus, and the pygmy or forest hippopotamus, Chceropsis. 

 The latter genus differs from its gigantic relative, in addi- 

 tion to its smaller size, by its much longer and more slender 

 legs, more laterally placed orbits, more circular nostrils, 

 longer tail, a lesser number of incisor teeth, and much larger 

 brain and a correspondingly larger brain-case in the skull. 

 The pygmy hippopotamus spends most of its time on land 

 in the thick forest growth, to which it retreats when alarmed. 

 The lateral position of the eyes and the circular nostrils are 

 differences in structure which do not fit it for an aquatic 

 life such as is passed by the larger genus. Hippopotamuses 

 of both genera were abundant in the Pliocene and Pleisto- 

 cene age in Europe, Asia, and North Africa. Fossil species 

 allied to the pygmy hippopotamus are known from the 

 larger islands of the Mediterranean and from Madagascar, 

 in which latter island they were the only ungulate and 

 practically the only land animal showing African affinities, 

 with the doubtful exception of the bush pig, whose status 

 as a native mammal is questionable. 



Key to the Races of amphibius 



Nasal bones narrow, their least width less than i}i inches; upper rim 

 of orbit less elevated, reaching at most 1% inches 



