Douglass : A Geological Reconnaissance. 



285 



Upper White 

 River. 



8 ft. 



Middle White 

 River "Oreodon 

 Beds. 



Lower White 

 River Beds. 



7- 

 6. 



5- 

 4. 

 3- 



contains irregular cavities (weathered pits) and 



root-like rods 



lo. Green sand with some nodules, gray on surface 



near top 38 ft. 



9. Gray shale, hard in places, sometimes greenish in 



color. Bones of Rhinoceros 24 ft. 



8. "Rubbly" sandstone in rounded, egg-shaped 



forms 4 ft. 



Harder sandstone than No. 6 5 ft. 



Fine greenish sand and clay, in one stratum 

 cracking vertically. Some imperfect horizontal 

 parting planes 12 ft. 



Green sand with sandstone concretions 6 ft. 



Green and gray clay shales 6 in. 



Fine gray sand, with some clay. Alerycoidodonts, 



Hyracodonts, Mesohipptis, etc 12 ft. 



Pinkish gray clay with brown cellular nodules. 

 " Oreodon " Beds — Iciops, Gymnopiychus^ Eu- 

 mys, Ischyromys, Paheolagus, Mesohippus, Hy- 

 racodon, Aceratherium, Alerycoidodonts, Leplo- 

 meryx, etc 32 ft. 



Tough sandy clay with appearance of stratification, 

 without brown nodules, but containing a few re- 

 mains of Merycoidodoitis. Probably belongs to 

 "Oreodon" horizon 6-8 ft. 



Total thickness of section 163 ft. 



Total thickness of Tertiary beds at White Butte 



about 320 ft. 



The Oreodon beds have nearly the same appearance wherever ex- 

 posed, but the overlying beds are more variable, and probably no two 

 sections would be just alike. The Oreodon beds at White Butte are 

 not rich in mammalian remains, and most of the fossils are fragmen- 

 tary, though in one place three skulls with portions of skeletons of 

 Merycoidodon, and a skull with part of a skeleton of Ictops were found. 

 In No. 3 of the last section, portions of the skulls of Merycoidodo7its 

 were obtained, but probably of different species from those of the nodu- 

 lar beds. No. 5 contains many remains of rhinoceroses. Two good 

 skulls were found, which have been referred X-oAceratherhim tridactyliim. 

 Some fragments of bones and teeth of reptiles and mammals, including 

 jaws of rodents and the tooth of a crocodile, were found in No. 6. 

 Fragments of bones were found in most of the higher horizons. 



Below is given a section of the Oligocene strata in the Little Bad 

 Lands southwest of Dickinson. It will be seen that it does not ex- 

 actly correspond with the sections at White Butte. 



