"CERATOPS beds" OF WYOMING AND MONTANA 263 



he designated as "Fort Union Nos. i, 2, and 3," respectively. The 

 lower member, or "No. i," and the middle member, or "No. 2," 

 together constitute the softer, darker colored shales and sandstones 

 with a combined thickness of about 1300 feet, while the upper member, 

 or "No. 3," consisting of massive sandstones interbedded with shales, 

 is more than 4000 feet thick and is identical with the whole of the Fort 

 Union as recognized by Stone in this section and earlier by Weed in 

 the Lebo Creek section. 



The lower and middle members were measured by Mr. Silberling 

 and myself in sec. 15, T. 6 N., R. 15 E., where the rocks are well 

 exposed, including the contacts with the "Laramie" gray sandstones 

 below and with the massive basal sandstone of "No. 3" above. On 

 account of the importance of the paleontologic collections obtained in 

 these members in adjacent townships where the succession is identical 

 it may be well to give the details. 



Section on branch of Fish Creek, Montana, in sec. 15, T. 6 N., R. 1 5 E. 

 "Fort Union No. 3." 



a. Massive sandstone forming base of this member. 

 "Fort Union No. 2." Feet. 



h. Shale with a few thin bands of sandstone 112 



c. Gray sandstone 5 



d. Shale _. 18 



e. Gray limestone, weathering brown 3 



/. Greenish gray shale with much soft sandstone of same color 



and brown ironstone concretions in lower third ; a few thin 

 bands of sandstone in upper part and several concretionary 

 layers near top 7°° 



838 

 "Fort Union No. i." 



g. Brown, thinly cross-bedded sandstone forming top of a con- 

 spicuous broken ridge 32 



h. Shale 200 



i. Greenish gray sandstone 15 



j. Greenish gray shale 249 



496 



Total thickness of Nos. i and 2 1334 



"Laramie." 



k. Rather soft, gray sandstone forming top of underlying formation. 



The lowest fossil plants listed by Knowlton as Fort Union came 

 from a bed about 50 feet above the base of Silberling's lower member 



