OF THE WHITE RIVER BEDS OF MONTANA. 



243 



more nearly correspond to the Oreodon division. Among the fossils are three very good 

 skulls of Oreodonts. One I have referred to the genus Eucrotaphus, one is a new species 

 of Oreodon and one is much like 0. culberlsoni. A good portion of the skeleton of the 

 latter was found, but there has not been time to clean it and make careful comparisons. 

 It is probable that it will have to be referred to a new species. 



These and other Oreodont remains were in the cracking, sandy clays which contain 

 nodular layers. A Titanotherium tooth was found in the same kind of clay but perhaps 

 a (rifle lower down. Colodon and Hyoznodon teeth and jaws were obtained, but I cannot 

 state with certainty their relation to the beds above mentioned. The strata here are con- 

 siderably disturbed, and in some places dip to the eastward as much as 80° to 40°. In 

 the ardent work of collecting I had not the time to study the geology of the region as 

 much as I hope to do later. Lying un conform ably on these deposits in places are nearly 

 horizontal strata of later date, either Miocene or Pliocene. 



Hycenodon montanus, sp. nov. 

 Oreodon robustum, sp. nov. 

 Eucrotaphus helence, sp. nov. 

 Colodon cingulatus, sp. nov. 



List of Fossils. 



Colodon, sp. 

 Mesohippus. 

 Titanotherium. 

 Cainopus (?). 



The Blacktail Deer Creek Beds. 



These are on Blacktail Deer creek, about thirty miles south and east of Dillon. The 

 exposure is small and only a few fossils were found. The material, as in the localities 

 previously mentioned, is mostly light colored and line grained, yet there are thin strata of 

 sandstone. None of the fossils positively determine the horizon. There was the new 

 genus Arretotherium, part of the back of a skull of Cainopus about the size of Aceratherium 

 tridactylum Ogborn, and part of a, mandible of Sleneofiber hesperus sp. nov. which is 



described in this paper. 



List of Fossils. 



Sleneofiber hesperus, sp. nov. Arretotherium acridem, gen. et sp. nov. 



Ccenopus (?). 



The skull of Sleneofiber complezus, described in this paper, came from the beds on the 

 west side of the Madison river above Three Forks (Douglass, 1809, p. 4). The locality is 

 about fifteen miles south of where the fossils occur in the Thompson Creek beds. Near 

 the same place were a femur, tibia, fibula and calcaneum of a rather long-limbed Perisso- 

 dactyl, probably a, rhinoceros, but the deposits here contain very few fossils. 



There are turtle remains in all the beds above described. 



