WHITE] CROW CREEK FOSSILS. 171 



Cope ill 1S7G. It is (le.seril)od and li.iiured in vol. ix of the United 

 States (k'ological Snl•^'c'y of the Teriitoiios. Only a few fraj^inents, 

 ■\vhieh I rcler to this species, were fonnd at the Crow Creek locality, 

 and only in No. 5 of that section. jMore perfect examjiles Avere foun<l 

 in the coal-bearing series constitnting the npi)er part of the Laramio 

 Group, near Evanston, Wyo., which I refer to this species. 



'Ko. 17. Plujsa felix White. 



Only two imperfect examples of this species were anywhere discovered, 

 and tliese only in bed No. 5 of the Crow Creek section. It seems to be 

 a tine I'lnjHa, yet the remarkable inllation of the body volution and a 

 pecnliaritv of its surface ornamentation suggest probably subgeneric 

 differences. See Bull. U. S. Geol. & Geog. Surv. Terr., Vol. IV, p. 714. 



ISTo. IS. Gouiohasis gracilicnta Meek & Hayden. 



Dr. Hayden also discovere<l this species in the Judith River beds ; 

 and it is figured and described in vol. ix of the United States Geological 

 Survey of the Territories. A goodly niunber of examples were found 

 in bed No. 5 of the Crow Creek section, which seem in all respects to 

 possess the typical characteristics of the species. Black Buttes Station, 

 \Vyo., is the only other locality at which the species has been recognized, 

 where it is found in strata of the upper portion of the Laramie Group, 

 but all the examiiles found there are more slender than the tyjies. 



No. 10. Goniohasis nebrascensis Meek & Hayden. 



This species was among the large collections made many years ago by 

 Dr. Hayden, from the Fort Union Group of the Upper Missouri Eiver 

 region. It is described and figured in vol. ix of the United States Geo- 

 logical Survey of the Territories. Both this species and G. ienuicarinata 

 of the same author, associated together as they are w^here they were 

 originally discovered, were obtained by one of the parties under Lieuten- 

 ant AYheeler's direction at Wales, Utah, and are described and figured iu 

 White's IJeport, vol. ix, Part I, Exploration and Siu^vey West of the One 

 Hundredth Meridian. G. nebrascemis was also recognized among some 

 fossils collected hy Prof. J. W. Powell from strata exposed in the Canon 

 of Desolation, of Green Elver, in Utah ; and the same species only 

 was found at the Crow Creek locality, and only in No. 5 of that section. 

 It is possible that G. tennicarinata is only a variety of G. nebrascensis^ as 

 has been suggested by Mr. Meek ; but if so it is an interesting tact that 

 the variation should be so i)recisely the same at the two very distant 

 localities where the two forms are so intimately associated, while the 

 characteristics that distinguish the last-named form are constant at all 

 the localities where it has been found. 



No. 20. MeJania icyomingensis Meek. 



INIr. ]Meek first discovered some imi)erfect examples of this fine shell in 

 the strata of the upper j)art of the Laramie Group, near Black Buttes 

 Station, Wyo., from which he described the species in the Annual 

 Eeport of the United States Geological Survey of the Territories, for 

 187-f, p. -jIG. In Professor Powell's lte])ort of the Geology of the LTinta 

 Mountains, published iu 1S7G, on page 131, I unwittingly described the 

 same species under the name of M. lunuidd, from some large and beau- 

 tifully preserved specimens that were obtained by Mr. W. Cleburn fi'om 

 the valley of Crow Creek some three years previously. Upon my own 

 examination of that region in 1877, I collected a number of specimens 

 of the same species from the same locality. I got fragments of it also 

 from the valley of Bijou Creek j besides which Mr. George L. Taylor, of 



