WANLESS— LITHOLOGY OF WHITE RIVER SEDIMENTS. 203 



vulcanism through the Tertiary Cordillera between the periods of 

 storm of the Eocene and Miocene will have to be amended. The 

 presence of a 200-foot bed mainly of volcanic glass and pumice 80 

 miles away from the nearest possible source of volcanic ejecta, and 

 more likely 200 to 400 miles distant from the eruptive volcanoes, 

 would hardly seem to indicate a period of quiet. Professor Sinclair's 

 description of a considerable thickness of andesitic tuffs and breccias 

 of Titanotherium beds age in the Wind River Basin of Wyoming 

 south of the Bridger-Owl Creek Range, is interesting in this con- 

 nection.^^ 



The only evidence of vegetation found fossilized so far in the Big 

 Badlands are a few hackberry seeds (Celtis), but Hatcher reports the 

 remains of a forest 12 miles north of the mouth of Corn Creek. 

 The plain was here and there dotted with small ponds in which fresh- 

 water algae and cyprid crustaceans were building up the limestone 

 beds of the series. 



Thus we have a general picture of the environment of one of our 



finest Tertiary mammalian faunas. 



Graduate College, 

 Princeton, N. J. 



^^ Bull. Am. Mus. Nat. History, Vol. 30, 191 1, pp. 99-102. 



