178 CONTRIBUTIONS TO CANADIAN PALAEONTOLOGY. 



PiiOLADOMYA suBVENTRicosA, Meek and Ilaydon. 



Pholadomya mM'enlricn.vi, Meek and Hayden. 1857. Proc. Ac. Nat. Sc. Phil., 



vol. IX., p. 142. 

 Plioladomya subiKiitricOKu, Meek. 187C. Kep. V. S. Geol. Surx'. Terr., vol. IX., 



p. 217, pi. :',f), figs. 8, a, b. 



North Saskatchewan Eiver, at Fort Pitt, and in Township 54, Eango 

 2, west of the 4th Principal Meridian, 1886 : one nearly perfect 

 specimen with botli valves ])ro8crved, from each of these localities. A 

 portion of a mould of a shell which may have belonged to this s])ecio.s, 

 was collected on the banks of the same river near the mouth of Moose 

 Hill Creek. 



Dv. Hector I'ecoi-ds finding a Pholadomija wliicli he rofcj-s to P. 

 occ/(i«/ifai/s of-Moi-l-on, but which is probably referable to this species, 

 at Fort Pitt, on the Noi'th Saskatchewan, and at the elbow of the 

 South Saskatchewan, in 1857 or 18."iS. 



LioptSTHA UNDATA, Mcok and Hayden. 



Pholiiflomija mtdata, Meek and Hayden. 185(i. Proc. Ac. Nat. Sc. Phil., vol. 



VIII., p. 81. 

 Pliolndoviya {CiimeUa) undata,Meek. 1864. Smitbson. Check-List N. Am. Cret. 



Inv. Foss., pp. 14 and 34. 

 LiopiMha {Cymell<i) xindala,Meek. 1876. Rep. U. S. Geol. Surv. Terr., vol. IX., 



p. 23G, pi. 39, figs. 1, a, b. 



Nose Creek, Township 37, Eange 9, west of the 4th Principal 

 Meridian, 1885 : one chai'ucteristic specimen. 



SoLECURTus (Taoehis) oocidentalts, Whiteaves. 



Plate 24, fig. 4. 



SolccuTlus (Tagdiis) ocdrfmto/i.f, Whiteaves. 1S87. Geol. and Nat. Hist. Surx. Can., 

 Ann. Rep., N. Ser., vol. II., p. 157 E. 



Shell transversely elongated, a little more than twice as long as 

 high, very nearly equilateral, strongly compressed at the sides, most 

 prominent on the umbonal slopes, and faintly dc]iicssed in the middle 

 below. Anterior and postej'ior ends both rounded at their mai'gins, 

 but rather moi'e broadly so below than above, while the (presumed) 



