WHITEAVES.] LARAMIE AND CRETACEOrS I.WERTEBRATA, 43 



Cytherea Jli'ssouriana, but with a queiy, and calK the latter bhell Bosinia 

 Missouriana. Under the circumstances it i» thought best to retain 

 Meek and Hayden's name for the Canadian bpeeimen>, first, because 

 they are much more like Meek's figures of C Deweyi than they are to 

 either ilortons or Whitfield's figures of Cytherea or Bosinia Missouri- 

 ana, and secondly, because they clearly do not belong to the genus 

 Bosinia. 



Mactra (Ct-MBOPHORa) TVarrenaxa, Meek and Hayden. 



M'ictro. Warrenana, Meek and Hayden. 1856. Proc. Ac. Xat. So. Phil., vol. 



VIIL, p. 271. 

 ^{actra { Cyrnbophora) Warrenana, Meek. 1S76. Eep. T.S. Geol. Surv. Terr., vol. 



IX., p. 208, pi. 30, fiv'S. 7, a, b, c, d. 



South Saskatchewan, five miles above Swift Current Creek, E. G-. 

 ilcConnell, 1883 : two specimens. Eoss Coul<Se, near Irvine Station, 

 on the Canadian Pacific Eailway, T. C. Weston, 1883 ; a single left 

 valve. 



iLiCTRA (CriiBOPHORA) GRACILIS, Meek and Hayden. 



^facli-agracili.%:Sleek and Harden. 1860. Proc. Ac. Xat. Se. Phil., vol. XII., 



p. 179. 

 Mactra {C'jmhoplirjro) gracrilis, Meek. 1S76. Eep. T S. Geol. .Surv. Terr., vol. IX., 



p. 209, pi. 17, figs. 18a, b. 



East Branch of the Poplar Eiver, on the J:9th Parallel (the place 

 called ••' Woody Mountain Astronomical Station" on page lOT of Dr. 

 Dawson's "Eeport on the Geology and Eesources of the country in the 

 vicinity of the 49th Parallel"), G-. M. Dawson, 1874, H.M. Xorth 

 American Boundary Commission : abundant and well preserved. 



LiopiSTHA (Ctmella) undata. Meek and Hayden. 



Tholadomya undata, Meek and Hayden. 1856. Proc. Ac. Xat. So. Phil, vol. 



VIIL, p. 81. 

 Liopistha {CymelUx) undata, Meek. 1870. Rep. L'.S. Geol. Sur\-- Terr., vol. IX., p. 



236, pi. 39, figs. 1, a, b. 



St. Mary Eiver, near its junction with the Bellj^ Rivei-, G. M. Daw- 

 son, 1881, and T. C. Weston, 1883. South Saskatchewan, opposite 

 mouth of Swift Current Creek, E. G. McConnell, 1882 : very abundant. 



