98 THE WHITE RIVER BADLANDS 



the name Chalicotherium (Beast of the Gravel). The teeth 

 were somewhat similar to those of the rhinoceros hence these 

 head parts were regarded as belonging to one of the un- 

 gulates. Some paleontologists believed at first that they 

 represented the artiodactyles but later they were generally 

 considered as representing the perissodactyls. The foot 

 bones continued to be regarded as belonging to the Edentates. 

 Filhol, a French paleontologist, in 1887 reflecting upon 

 the fact that Macrotherium foot bones were not uncommon 

 and that Chalicotherium teeth were pretty well known but 

 that no one had discovered feet of the latter nor head 

 of the former, began to suspect that the two represented 

 the same creature. The discovery a little later of nearly 

 complete skeletons under favorable conditions definitely 

 established the correctness of this supposition. It is of 

 interest that in more recent years American discoveries 

 have added greatly to our knowledge of these strange 

 creatures. Several localities have afforded remains of 

 which the most important has been the famous Agate 

 Springs locality in northwestern Nebraska. The de- 

 posits are known as the Harrison beds. Director W. J. 

 Holland and Mr. O. A. Peterson of the Carneige Museum in 

 1909 described in elaborate manner some of the best Agate 

 Springs material found up to that time and summarized in 

 good form the descriptions given in the publications of 

 other investigators. Later the American Museum of Natural 

 History made important discoveries in the Agate Springs 

 locality and in their five summers ( 1911-1914, 1916 ) of exca- 

 vation unearthed there within an area of about thirty-six 

 feet square nearly complete skulls of ten individuals and 

 skeletal parts of seventeen individuals. This material added 

 new information of importance until now the size and na- 

 ture of the animal are known to a high degree of certainty. 



All of the chalicotheres found in the Agate Springs 

 quarries have been designated as belonging to the genus 

 Moropus. Several species have been described. The largest 

 is Moropus elatus, an animal as large or larger than the 

 African rhinoceros. (Plate 31). Others are considerably 

 smaller. 



Moropus in life was evidently very grotesque in appear- 

 ance. The head resembles not a little that of the horse, or 

 the primitive rhinoceros. The neck is heavier than that of 



