1 28 STANTON & KNOWLTON — LARAMIE AND RELATED FORMATIONS. 



with the lower Tertiary, although still regarded by some as belonging to 

 the Laramie series. The Laramie as thus characterized was supposed 

 to be very sharply circumscribed, but soon it was pointed out that cer- 

 tain of the lower coal-bearing members appeared to be in some cases 

 included in the Fox Hills, or uppermost marine Cretaceous — that is, that 

 there had been alternations of fresh and salt water conditions before the 

 true Laramie age prevailed. As more detailed studies were made in 

 Laramie areas it came to be evident that still further differentiation of 

 the so-called Laramie was possible. In this way the Arapahoe and Den- 

 ver formations have been removed and characterized by Messrs Eldridge 

 and Cross in Colorado and the Livingston formation by Weed in Mon- 

 tana, and it appears possible in the light of investigations now in progress 

 that even still further differentiation of the original Laramie will be found 

 necessary. 



As many of the supposed typical Laramie localities had been visited 

 and studied by the various investigators some years ago, before the recog- 

 nition of the Arapahoe, Denver, and Livingston formations, it became a 

 matter of interest and importance to revisit these places and ascertain, 

 if possible, the bearing of the new data on the questions of their distri- 

 bution, life, etcetera. Other areas of later discovery, referred somewhat 

 vaguely to the Laramie, had also been brought more or less in question, 

 and the authors of this paper undertook an examination of various Lara- 

 mie localities in Colorado, Wyoming, and Utah during the past season 

 in hope that the two branches of paleontology represented might by being 

 worked in conjunction lead to definite results. 



As a preliminary to this study, we visited the type localities of the 

 Arapahoe and Denver formations in the vicinity of Denver, Colorado, 

 and familiarized ourselves with their stratigraphic and lithologic appear- 

 ance. We also visited one of the well known localities for the supposed 

 true Laramie on Crow creek in northeastern Colorado. We then studied 

 in succession the Ceratops beds of Converse county, Wyoming, the Lara- 

 mie plains (including the localities at Harper Station and vicinity, and 

 Cooper and Dutton creeks), Carbon, Black Buttes, Point of Rocks, Rock 

 Springs, Hams Fork, and Evanston in Wyoming, and Coalville, Utah. 



Ceratops Beds of Converse County, Wyoming. 

 stratigraphy and local development. 



The stratigraphy of this region has been well described by Mr J. B. 

 Hatcher,* whose sketch map showing the boundaries of the formation 



*The Ceratops Beds of Converse County, Wyoming: Am. Jour. Sci., 3d ser., vol. xlv, pp. 135-144, 

 February, 1893. Some localities for Laramie Mammals and Horned Dinosaurs: Am. Naturalist, 

 vol. xxx, pp. 112-120, February, 1896. 



