44 CONTRIBUTIONS TO CANADIAN PALEONTOLOGY. 



Bull's Head, about twenty-two miles west of the west end of the Cypress 

 Hills, E. G. McOonnell, 1883 : abundant. Berry Ci-eek, Township 

 25, Eange 12, and four miles south of Battle Elver, Township 38, be- 

 tween Eanges 12 and 13, both west of 4th Meridian, J. B. Tyrrell, 

 1884. Three miles north of Eoss Coulee, near Irvine Station, on the 

 Canadian Pacific Eailway, T. C. Weston, 1884; abundant. 



A very common and widely distributed species in the Upper Cre- 

 taceous rocks of the Canadian Xorth West. 



Ne^era Moreatjensis, Meek and Hayden. 



Corhula Moreaiiends, Meek and Hayden. 1856. Proc. Ac. Nat. So. Phil., vol. 



VIII., p. S3. 

 jSlexra Mureaitenm, Meek and Hayden. 18(30. lb., vol. XII., p. 185. 



Meek. 1876. Hep. U.S. Geol. Surv. Terr., vol. IX. p. 239, 



pi. 17, figs. 11a, b, c. 



Whitfield (as of Meek), Pal. Black Hills, Dakota, p. 420, pi. 



11, fig. 81. 



Old Wives Creek, Township 10, Eange 11, west of Third Principal 

 Meridian, E. G. McConnell, 1884: two specimens. 



Panop.ea subovalis. (N. Sp.) 



Plate 6, figs. 6 and 6 a. 



Shell nearly equivalve, rather strongly convex, most prominent a 

 little above the middle, and slightly in advance of the mid-length, 

 oblii|uely compressed behind ; lateral outline transversely and broadly 

 suboval; length not quite one-third more than the maximum height; 

 posterior termination of the valves gaping. Anterior side a little 

 shorter than the posterior, its outer margin subangular at its junction 

 with the suj)erior border above, and retreating obliquelj' and rapidly 

 both inwards and downwards in a broadly convex curve to the base 

 below; posterior side abruptly contracted, its margin nearly straight 

 above but rounding up very rajjidly from the base below, its gaping 

 termination narrow and subtruncated somewhat obliquely above the 

 middle of the valves. Ventral margin broadlj' and convexly arched, 

 rounding up rapidly at each extremity : superior border descending 

 gradually in front of the beaks, and nearly straight behind ; umbones 

 moderately prominent; beaks placed a little in advance of the middle, 

 apparently I'ather small and incurved, with a slightly forward inclina- 

 tion. 



