456 



THE AGE OF MAMMALS 



living types at 

 desert, while the 



Hay Springs, at Silver Lake, and in the Oregon 

 more recent fauna of Washtucna Lake, Washington, 



shows a large proportion 

 of forest and mountain 

 types and no aquatic mam- 

 mals. 



Hay Springs, Nebraska. 

 — The Hay Springs (Fig. 

 194, 24) fauna, as explored 

 by the American Museum 

 expeditions of 1893 and 

 1897, is a very rich one 

 and may be taken as t^^^ical 

 of the early phase of the 

 Equus Zone. It includes 

 the llama-like cameloids 

 (Camelops) and a true camel 

 (C americanus). The true 

 prong-horn antelopes {An- 

 tilocapra) make their first 

 appearance here, and with 

 them are associated the 

 smaller Capr ornery x (C 

 furcifer), an animal inter- 

 mediate between the mery- 

 codonts (see pp. 294-5, 

 357) and the true American 

 prong-horns. The most 

 abundant species of horse 

 is E. complicatus, while 

 E. fraternus, a smaller ani- 

 mal, is also found. The 

 sloth which appears here 

 is distinct from the mid- 

 Pleistocene Af^/Zorfon harlani 

 of the East, and according 

 to the determination of 

 Brown belongs to a dis- 

 tinct genus, Paramylodon} 



1 Matthew, W. D., List of the 

 Pleistocene Fauna from Hay 

 Springs, Nebraska. Bull Amer. 

 Mus. Nat. Hist., Vol. XVI, 1902, 

 pp. 317-322. 



