Mesozoic and Ccenozoic Geology and Pala;ontology. 191 



In 1858, Dr. F. V. Hayclen* prepared a vertical section, showing- 

 the orclei' of superposition of the different beds of the Tertiary Basin 

 of Wliite.aud Niobrara rivers. The Miocene, ho divided, in ascending- 

 order, as follows: 



1. Bed A. — Light gra}-, fine sand, with more or less calcareous 

 matter, passing down into an ash-colored plastic clay, with large 

 quantities of quartz grains disseminated through it, sometimes form- 

 ing aggregated masses like quartzose sandstone cemented with plaster; 

 then an ash-colored clay with a greenish tinge, underlaid at base by a 

 light gray and ferruginous silicious sand and gravel, with pinkish 

 bands. Immense quantities of silex, in the form of seams, all through 

 the beds. Titanotherium Bed. Found on Old Woman's creek, and in 

 man}^ localities along the valley of the South Fork of Shyenne. Best 

 development on Sage and Bear creeks. . Seen at several localities in 

 the valley of White river. Thickness, 80 to 3 00 feet. 



2. Bed B. — A deep flesh-colored, argillo-calcareous, indurated grit; 

 the outside, when weathered, has the appearance of a plastic claj^ 

 Passes down into a gray cla}-, with layers of sandstone; underlaid by a 

 flesh-colored, argillo-calcareous stratum, containing a profusion of 

 Manjmalian and Chelonian remains. Turtle and Oreodon Bed. Found 

 on Old Woman's creek, a fork of Shyenne river, on the head of the 

 South Fork of the Shyenne; most conspicuous on Sage and Bear 

 creeks, and at Ash Grove Spring, and well developed in numerous 

 localities in the valley of White river. Thickness, 80 to 100 feet. 



3. Bed C. — Very fine, yellow, calcareous sand, not diflfering very 

 materially from Bed D, with numerous layers of concretions, and 

 rarely organic remains, passing down into a variegated bed, consisting 

 of alternate laj^ers of dark brown clay, and light gray, fcalcareous grit, 

 forming bands, of which twenty-seven were counted at one locality, 

 from one inch to two feet in thickness. Found on White river, Bear 

 creek. Ash Grove Spring and head of Shyenne river, but most con- 

 spicuous near White river. Thickness, 50 to 80 feet. 



4. Bed D. — A dull, reddish-brown, indurated grit, with many layers 

 of silico-calcareous concretions, sometimes forming a heav^^-bedded, 



* Proc. Acad. Nat. Sei., vol. x. 



