THE STORY OF THE HORSE 229 



reaches his modern splendid development. During 

 the early Quaternary the horse was perhaps in some 

 of his representatives a larger creature than he is to- 

 day. Each foot now has but a single toe. The nail 

 has spread around firmly and heavily, until it has be- 

 come a splendidly developed hoof, permitting the ani- 

 mal to travel with speed over firm and often stony 

 ground. The side toes have disappeared completely 

 from the outside of the horse's leg, although upon re- 

 moving the skin it is easy to find the long splints, 

 which are the remnants of toes, which have not yet 

 quite disappeared. His heel has been lifted in the air 

 until it is eighteen inches off the ground, and he is 

 standing like an expert dancer upon the tip of his toe. 

 The body of the horse thus being lifted far off the 

 ground, a new development becomes necessary. All 

 through the growth of the creature the neck and head 

 have been obliged to lengthen correspondingly. Every 

 animal must be able to bring its head down to the 

 level of its feet in order that it may drink. Various 

 animals use different methods to accomplish this re- 

 sult. The giraffe, with his enormously long legs, has 

 a correspondingly long neck, which lowers his mouth 

 to the ground. Even with this extended neck the 

 giraffe's legs are so exceedingly long that he is obliged 

 to spread his front feet when he wishes to reach tlic 

 ground with his head. The elephant has pursued ex- 



