CHAPTER X 



THE HIPPOPOTAMUS 



Hippopotamuses 

 Family Hippopotamidce 



The members of the family Hippopotamidcs are per- 

 haps best described as hairless, thick-skinned mammals of 

 large size related to the pigs. They are, however, only 

 distantly related to pigs, from which they differ in many 

 fundamental ways, chief of which are the primitive con- 

 dition or evenly four-toed character of the feet, the lateral 

 toes of which reach the ground and assist in supporting the 

 body weight. The head differs decidedly from that of the 

 pigs by the absence of a terminal disk to the snout and by 

 the enormous enlargement of the lower jaw. The canines 

 are developed into large tusks, the tips of which come in 

 contact inside of the lips. The incisor teeth grow into 

 long spikes, which do not meet or function as grass- 

 cutters, the great square lips with their horny edges 

 performing the work of grazing. The molar teeth are 

 transversely ridged and small, the last one showing no 

 tendency toward the lengthening and complication found 

 in the pigs. The body is long and barrel-shaped, and sup- 

 ported on very short legs placed far apart, making loco- 

 motion slow. The head is very peculiar, being quite square 

 in front, flat on top, with an enormous mouth and lower 

 jaw of immense proportions. Placed rather high and near 



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