ii6 



E E. Clements 



Though noting the differences between the faunas of Rancho 

 La Brea and Fossil Lake deposits, Hay concludes that those of 

 the latter also belong to the Aftonian (1927:191), in spite of the 

 indications that it was more desert-like and colder. It seems 

 probable that these and other discrepancies already noted are to 

 be explained by smaller differences in the climates of the Pleisto- 

 cene of the Far West and less clearly marked limits between 

 glacial and interglacial stages. When allowance is made for the 

 wet and dry phases of the climatic cycles, it appears that the 

 latter half of the Pleistocene differed litde from the present over 

 the vast stretch of the grassland climax. 



Ungulates — 

 Hipparion mohavense 

 Hipparion spp. 2 

 Pliohippus tantalus 

 Pliohippus fairbanksi 

 Pliohippus sp. 



Proboscideans — 

 Tetrabelodon ? sp. 



Rodents — 

 Lepus ? sp. 



PLIOCENE 



RiCARDO 



MAMMALS 



Procamelus spp. 2 

 Pliauchenia sp. 

 Alticamelus ? sp. 

 Merycodus near necatus 

 Merycochoerus ? californicus 



Thousand Creek 



MAMMALS 



Ungulates — 



Pliohippus ? sp. 



Equus ? sp. 



Camel, cf. Camelus americanus 



Pliauchenia ? sp. 



Sphenophalis nevadensis 



Proboscideans — 

 Tetrabelodon ? sp. 



Ilingoceros alcxandrae 

 Ilingoceros schizoceras 

 Teleoceras ? sp. 

 Prosthennops ? sp. 



