ALONG FOUR-FOOTED TRAILS 



On one of these trips, as Long Bob and 

 his companion rode along the edge of a broad 

 alkali bed, they met a wise-looking little man 

 who said he was from an eastern college and 

 had come west in the interest of science to 

 search for fossil animals. He explained to 

 Long Bob and the much interested school 

 teacher that ages ago the western plains were a 

 country composed of many comparatively shal- 

 low lakes bordered with rank, weedy marshes 

 and that from the fossil remains that had been 

 found in this and preceding periods of the 

 earth's history it has been proven that the an- 

 tecedent of the horse was a little animal about 

 the size of a fox, having four toes and a very 

 large head. This period marked the beginning 

 of the great group of vertebrate animals which 

 includes man, the mammals. As the earth's 

 surface gradually changed the horse, through the 

 process of evolution, adapted itself to its envi- 

 ronment ; thus it passed through gradual stages 

 of animal growth as the strongest and fleetest 

 of its kind. In its upward progress there was an 

 increase in stature and the size of the brain. 

 As the food changed the teeth grew more com- 

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