1917 ] Merriam: Pliocene Mammalian Faunas 435 



Edentata 



Glyptotherium texanum Osborn 



Megalonyx leptostomus Cope 

 Proboscidea 



Trilophodon? (Gomphotherium) shepardii Leidy 



Dibelodon (Stegodon) mirificus Leidy 



?Dibelodon tropicus Cope 



?Dibelodon praecursor Cope 



?Dibelodon humboldtii (Cuvier) 

 Equidae 



Pliohippus simplicidens (Cope) 



Protohippus ?, minutus (Cope) 



Pliohippus cumminsii (Cope) 



Neohipparion, sp. 

 Diootylidae 



Platygonus bicalearatus Cope 



Platygonus texanus Gidley 

 Camelidae 



Pliauchenia spatula Cope 



Pliauchenia, sp. 



Characteristic of the Blanco is the presence of advanced horses 

 of the most progressive type of Pliohippus with Neohipparion, of ad- 

 vanced mastodontine types near Stegodon, of very advanced dogs of 

 the Borophagns type, and of two types of edentates. This fauna is 

 also characterized by absence of oreodonts and rhinoceroses. 



Most important of all Pliocene mammal assemblages of America is 

 the Snake Creek fauna 15 of western Nebraska obtained from beds con- 

 sidered to represent a part of the Ogallalla formation of Dart on. 

 From this formation over seventy species are known at present and 

 the wealth of material leads one to hope that the number may be 

 further increased by future collecting. 



The varied fauna of Snake Creek may be listed as follows: 



Snake Creek Fauna 



Dogs 



Amphieyon amnieola Matthew and Cook 

 Amphieyon, sp. indet. 

 ?Amphicyon, sp. indesc. 



Aelurodon haydeni validus Matthew and Cook 

 Aelurodon saevus secundus Matthew and Cook 

 Aelurodon, cf. wheelerianus Cope 

 Aelurodon, sp. div. indet. 



Tephroeyon hippophagus Matthew and Cook 

 Tephrocyon, ef. temerarius Leidy 

 Canis, ef. vafer Leidy 



is Matthew, W. D., and. Cook, IT. J., Bull. Amer. Mus. Nat. Hist., vol. 26, pp. 

 361-414, 1909; Sinclair, W. J., Additions to the fauna of the Lower Pliocene 

 Snake Creek beds (results of the Princeton University 1914 expedition to 

 Nebraska), Proc. Amer. Philos. Soc, vol. 54, pp. 73-95, 1915. 



