C. A. White — On the Bear River Formation, etc. 95 



In 1876 also Major J. W. Powell, who had personally exam- 

 ined the geology of the district embracing the lower portion of 

 Sulphur Creek and the adjacent portion of Bear River valley 

 accepted the conclusions which Mr. Meek had reached con- 

 cerning the order of superposition of the members of the 

 Sulphur Creek section, and published a verbatim copy of 

 Meek's description of it.* In this publication Major Powell 

 assigned the Bear .River strata to his Point of Rocks Group, 

 which is equivalent to the Laramie, but both of which he 

 assigned to the Cretaceous, placing the Bear River strata at 

 the summit of the Sulphur Creek- section, as all the other 

 geologists referred to had done. In the same volume I de- 

 scribed several of the characteristic molluscan species of the 

 Bear River formation, f 



In certain of my writings which were published in 1877 

 and 1878 I assigned the strata which I now designate as the 

 Bear River formation, as well as the coal-bearing beds near 

 Evanston, which are also found in Bear River valley, to the 

 great Laramie formation.;}; Both of these assignments, how- 

 ever, having been erroneous a part of the conclusions which 

 were reached in their discussion were necessarily also erroneous. 



The results of some extended field observations made by 

 myself in Colorado, Utah and Wyoming were published in 

 1879. § In the part of that publication which relates to the 

 geology of Bear River valley I expressed the views which I 

 then held concerning the relation to the Laramie formation of 

 the Bear River strata and of the Evanston coal- bearing beds. 

 These views were similar to those expressed in my publications 

 of the two previous years except that in the later publication I 

 suggested that the Bear River strata are older than the Laramie ; 

 but I based this opinion more upon paleontological, than upon 

 stratigraphical ground. I repeated the expression of this 

 opinion in 1883.| 



In 1879 Dr. A. C. Peale published the results of his exam- 

 ination of the geology of a portion of western Wyoming,^" in 

 which publications he shows that the Bear River formation has 

 a greater geographical extent than was ever before known. 

 He found these strata occupying a belt of country of varying 

 width, lying partly in Wyoming and partly in Idaho, and ex- 

 tending northward from near the place of their original dis- 



* Geology of the Uinta Mountains, p. 158. 

 f Geology of the Uinta Mountains, pp. 11-8, 122, 123. 



% Bull. U. S. Geol. Surv. Terr., vol. iii, pp. 607-614. lb., vol. iv, pp.. 707-724. 

 § Eleventh Ann. Rep. U. S. Geol. Surv. Terr., pp. 161-172. 

 I Third Ann. Rep. U. S. Geol. Surv , p. 430. 



■j[ Eleventh Ann. Rep. U. S. Geol. Surv. Terr., pp. 5 1 1 -644 ; and map accom- 

 panying the 1 2th Ann. Rep. Also Bull. U. S. Geol. Surv. Terr., vol. v, pp. 1 95-200. 



