Conclusion 269 



I secured this noble representative of American 

 Elephants in June, 1908 (Fig. 44). 



How rich are the strata that compose the earth's 

 crust only a fossil hunter can fully realize. Take, 

 for instance, western Kansas, where the soil beneath 

 our feet is one vast cemetery. I know of a ravine 

 in Logan County which cuts through four great for- 

 mations. The lower levels, of reddish and blue 

 chalk, are filled with the remains of swimming liz- 

 ards, with the wonderful Pteranodonts, the most 

 perfect flying machines ever known, with the 

 toothed bird Hesperornis, the royal bird of the 

 West, and the fish-bird Icthyornis, with fish-like bi- 

 concave vertebrae, with fishes small and great (one 

 form over sixteen feet long), and huge sea-tortoises. 

 Above are the black shales of the Fort Pierre Cre- 

 taceous, thousands of feet of which are exposed in 

 the bad lands of the upper Missouri. In this forma- 

 tion the dinosaurs reign supreme. Still higher are 

 the mortar beds of the Loup Fork Tertiary, where 

 the dominant type changes from reptiles to mam- 

 mals. Here, in western Kansas, are found great 

 numbers of the short-limbed rhinoceros, the large 

 land-turtle, Testudo orthopygia, several inferior 

 tusked mastodons, the saber-toothed tiger, the three- 

 toed horse, and a deer only about eighteen inches 

 high. Higher still, where the grass roots shoot 

 down to feed on the bones, are the Columbian mam- 



