TOP OF THE LARAMIE. 155 



Anemia subcretacea, (Sap.) Gard. & Ett. Myrica torreyi, Lx. 



Sequoia reichenbachi, Gein. Quercus acrodon, Lx. 



B r achy phy Hum, n. sp. Ficus planicostata, Lx. 



Salix sp. Cinnamonum affine, Lx: 



Spathites, n. sp. (?). Celastrus, n. sp. 



Of these 10 species 4, including 3 new to science, have not been found 

 outside these beds, while all of the remaining species have been found in 

 either the Point of Rocks or Coalville beds. 



From the foregoing presentation it appears that the flora of the Mon- 

 tana formation embraces at least 67 species. 



TOP OF THE LARAMIE. 



Until a few years ago it was the custom to include in the Laramie all 

 of the beds between the Fox Hills and Wasatch formations. In the 

 Denver region the detailed studies of Cross and Eldridge,* already referred 

 to, have resulted in the recognition of the Arapahoe and Denver beds 

 separated from the Laramie and from each other by unconformities and 

 distinguished by marked lithologic features. A revision of the fossil 

 floras of that region has also shown that the Denver beds contain a flora 

 composed of species a large proportion of which are not found in the 

 underlying Laramie. Cross, f Hills, % and others have observed that beds 

 lithologically resembling the Denver bed and in a similar stratigraphic 

 position above the Laramie occur at several widely separated localities 

 in western and southwestern Colorado. In southern Montana Weed § 

 has defined the Livingston formation as a very thick series of strata litho- 

 logically comparable with the Denver beds, resting unconformably on 

 the Laramie and yielding a small flora more closely related to the Den- 

 ver flora than to any other. The same geologist || also finds beds that 

 he refers to the Fort Union, overlying the Livingston. All these forma- 

 tions are older than the Wasatch, and we should naturally expect to find 

 them in eastern and southern Wyoming, or, if they are absent there^ 

 their places should be indicated by unconformities. 



The Denver and Arapahoe beds have yielded representatives of a re- 

 markable reptilian fauna consisting largely of horned dinosaurs of the 

 family Ceratopsida?. The presence of this family in the Ceratops beds 

 of Converse county and probably at Black Buttes has suggested the 



* Proc. Colo. Sci. Soc, vol. iii, pt. i, pp. 86-133 ; Am. Jour. Sci., 3d ser., vol. xxxvii, 1889, pp. 261- 

 282 ; Monograph xxvii, U. S. Geol. Survey (in press), 

 t Am. Jour. Sei., vol. xliv, 1892, pp. 19-42. 

 % Proc. Colo. Sci. Soc, vol. iii, pt. iii, 1890, pp. 390-397. 

 gBull. U. S. Geol. Survey, no. 105, pp. 21-37. 

 || Am. Geologist, vol. xviii, pp. 201-211, October, 1896. 



