white.] CEOW CEEEK FOSSILS. 171 



Cope in 1876. It is described and figured in vol. ix of the United 

 States Geological Survey of the Territories. Only a few fragments, 

 which I refer to this species, were found at the Crow Creek locality, 

 aud only in No. 5 of that section. More perfect examples were fount! 

 in the coal-hearing series constituting the upper part of the Laramie 

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



No. 17. Pliysafelix White. 



Only two imperfect examples of this species were anywhere discovered, 

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

 a true Physa, yet the remarkable inflation of the body volution and a 

 peculiarity of its surface ornamentation suggest probably subgeneric 

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



No. 18. Goniobasis gracilienta Meek & Hayden. 



Dr. Hayden also discovered this species in the Judith Eiver beds ; 

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

 Survey of the Territories. A goodly number 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, 

 TVyo., 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 examples found there are more slender than the types. 



No. 19. Goniobasis 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. tenuicarinata 

 of the same author, associated together as they are where they were 

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

 ant Wheeler's direction at Wales, Utah, and are described and figured in 

 White's Eeport, vol. ix, Part I, Exploration and Survey West of the One 

 Hundredth Meridian. G. nebrascensis was also recognized among some 

 fossils collected by Prof. J. W. Powell froni strata exposed in the Canon 

 of Desolation, of Green Eiver, 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. tenuicarinata is only a variety of G. nebrascensis, as 

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

 the variation should be so precisely 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. Melania icyomingcnsis Meek. 



Mr. Meek first discovered some imj)erfect examples of this fine shell in 

 the strata of the upper part 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 

 18 72, p. 510. In Professor Powell's Eeport of the Geology of the Uinta 

 Mountains, published in 1870, on page 131, I unwittingly described the 

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

 tifully preserved specimens that were obtained by Mr. W. Cleburn from 

 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 ; besides which Mr. George L. Taylor, of 



