270 Life of a Fossil Hunter 



moth, the one-toed horse, like our species of to-day, 

 a camel like our South American llama, and a bison 

 far larger than the present species. 



The living bison has become almost extinct itself, 

 through the agency of man. And in the layer of 

 soil which covers all these formations, an old arrow- 

 head and the crumbling bones of a modern buffalo 

 give an object lesson in the manner in which these 

 relics of the earlier world have been preserved. So 

 races of animals, as of men, reach their highest state 

 of development, retrograde, and give place to other 

 races, which, living in the same regions, obey the 

 same laws of progress. 



My readers will be pleased, I am sure, to know 

 that just before these pages go to press I am per- 

 mitted to tell the story of our last great hunt in Con- 

 verse County, Wyoming, during July, August, and 

 September, 1908, for the largest skull of any known 

 vertebrate, the great three-horned dinosaur, Tricera- 

 tops (Fig. 45). Only thirteen good specimens are 

 known to American museums, 7 of which are in Yale 

 University Museum, and were collected, I believe, by 

 J. B. Hatcher. From his field notes Mr. Hatcher 

 has made a map of this region with crosses to in- 

 dicate the localities in which skulls have been found, 

 and 30 are so indicated, but I soon learned that he 

 noted broken and poor material, as well as the more 

 perfect. With my three sons I entered the region 





