WHiTEAVES.] LARAMIE AND CRETACEOUS INVERTEBRATA. 5 



The muscular impressidns and hinge dentition of this shell l.ieing 

 unknown, it is. of course, not Cjuite certain whether it is an Anoinia or 

 not. Dr. C. A. White, who has soeu the specimens, thinks it is a 

 Placunanoviia, of the suligenus Monia, Gray. 



OsTREA GLABRA, Meek and Harden. 



Ostrfi, ijhihni, :Meek lV Hayden. 1S57. Proc. Ac. Kat. So. Phil., vol. IX., p. 146. 

 CMre" Wyomiagmsis, Meek. 1S73. Eep. U. S. Geol. Surv. Terr, for 1S72, p. 508. 



Illustrated by Dr. C A. White on pi. 20 of Contr. to PaL 



(U.S. Geol. Sun-., 18S0), Xos. 2 to S. 

 Ostrea arci'otUis, ileek. 1873. Eep. U.S. Geol. Surv. Terr, for 1S72, p. 477. 

 Ostreo glahro, Meek. 1876. Bep. U.S. Geol. Surv. Terr., vol. IX., Rep. Inv. Cret. 



and Tert. Foss. U. 3Iiss. Cy., p. 509, pi. 40, figs. 2, a, b, e, d. 

 O^tno hisecurls, White. 1876. Povi-ell's Rep. Geol. Uinta Mts., p. 112. Illustrated 



on pi. 21 of Dr. C. A. White's Contr. to Pal., Xos. 2 to 8. 

 Ostrea glah-a, White, (as of M. ><: H.) 1880. U.S. Geol. Surv., Contr. to Pal, Xos. 



2 to 8, p. 56. 

 Osirea glabra, White, (as of M. & H.) 1883. Rev. Xon-INIarine Foss. Moll. X. 



Am., pis. 9, 10, 11 and 12. 



Bow Eiver, mouth of East Arrow-wood Creek, G-. M. Dawson, 1881 : 

 Upper Belly Eiver, twenty-two and twenty-three miles above the mouth 

 of the Waterton, E. G. iicConnell, 1881; St. ilary Eiver Series. High 

 Eiver five miles above the forks, E. G. McConnell, 1882 : Forks of 

 Devil's Pine and Three Hills Creeks, also Bed Deer Eiver, near 

 8th correction line, J. B. Tyrrell, 1884. Oyster Creek, N. W. 

 branch of the north fork of the Old Man Eiver, G. M. Dawson, 1884. 

 This last locality is in a nearly isolated basin in the mountains, 

 and the horizon is not certainly that of the St. Mary Eiver Series. 



Most of the specimens from these localities belong to the variety 

 Wyomingensis. 



A single valve of an oyster collected by Prof. Macoun from a layer 

 of limestone in the Hand Hills, in Township 2s, Eange 17, west of 

 the 4th Meridian, may also be referable to this variable species. 



OsTREA SDBTRiGONALis, Evans and Shumard. 



Osirea mbirigomilis, Meek, (as of E. & S.) 1876. Eep. U.S. (4eol. Surv. Terr., vol, 

 IX., Rep. Inv. Cret. & Tert. Fuss. U. 3Iiss. Cy., p. 510. 

 pi- 40, figs, a, b, c, d. 

 " " White. 1883. Rev. Xon-marine Foss. ^Moll. X. Am., pi. 12, 



figs. 2-5. 



