XI. SOME HOOFED ANIMALS 



The feet of mammals, if contrasted, afford an interest- 

 ing study, showing the curious modifications which adapt 

 the milk givers to many strange and opposite conditions 

 of life. The feet of the whale have disappeared, and 



those of the seal are 

 more like fins. In 

 the moles they are 

 digging machines, 

 in the bat they are 

 adapted to clinging, 

 and in the duck 

 moles they are pad- 

 dles. Many, as in 

 the kangaroos, are 

 formed for leaping. 

 Almost every diver- 

 sity is found, and 

 none are more interesting than those called hoofs (Fig. 82), 

 in which the toes are encased in horny enlargements, or 

 are provided with blunt, padlike nails. A similar compari- 

 son of entire limbs is not without interest. 



The hoofed animals include a large number valuable 

 to man, as the horse, camel, pig, elephant, and others. 

 The hyrax (Fig. 83) is one of the smallest, not much 

 larger than a rabbit ; yet it has feet which recall those of 

 the rhinoceros, being protected by pads. The toes, four 



100 



Fig. 82. — Hoof of a Horse. 



