33 



in the posterior margins of the ralves. They are also much 

 tliiuner shells. 



380 = Corbula (sp. ined.), Owen, Second Rept. Geol. Survey Arkansas, 



pi. viii, fig. 1. 



381 = Cardium ? sancti-sabae, Roemek, Kreid. Vou. Tex. 1852, 48, vi, 7. 



This is not a true Papyridea, and it is very doubtful whether 

 it can go into the group Liojyisiha. 



404 — The genus Tancredia differs so materially from the Cardiidae, Luci- 



nidae, Isocardiidie, &c., to which it has been respectively referred, 

 that we are probably less liable to err in keeping it separate as 

 the type of a distinct family. 



405 := Cyprina arenaria, Meek & Hatden, Proc. Acad. Nat. Sci. May 



1857, 143. 



409 = Cyprina humilis, Meek & Hatdex, ib. May 1860, 179. 



The name Cyprinidse, having been in use for a family of fishes, 

 since 1831, cannot be retained for this family ; I would, there- 

 fore, propose to call it Veniliidae. 



410 := Venilia quadrata, Gabb, Proc. Acad. Nat. Sci. Nov. 18G1, 3C4 (not 



Cyprina quadrata, D'Orbigny, 1843, which is a true Venilia'). 

 412 = Cyprina subtumida, Meek & Hayden, Proc. Acad. Nat. Sci. May 

 1857, 144. 



416 = Cyprina Laphami, Shumard, Proc. Bost. Soc. Nat. Hist. Sept. 1861. 



417 = Venus? circularis, Meek & Hayden, ib. Nov. 1856, 27. 



425 = Callista eufalensis, Cokrad, Jour. Acad. sec. ser. IV, 285, xlvi, 24. 



426 = Cytherea De^weyi, Meek & Hayden, Proc. Acad. Nat. Sci. April 



1846, 83. 



427 ^ Cytherea leonensis, Conrad, Mex. Bound. Rept. I, part 2, 1858, 



153, vi, 1. (Wrongly printed hnonensis on p. 13 of the List.) 



428 ^ Cytherea lamarensis, Shumard, Trans. St. Louis Acad. Sci. I, 



p. 600. 



429 = Cytherea missouriana, Mokton, Jour. Acad. Nat. Sci. sec. ser. 



VIII, 120, ii, 2. 



430 = Cytherea nebrascensis, Meek & Hayden, Proc. Acad. Nat. Sci. 



April 1856, 83. 



431 = Cytherea orbiculata, Hall & Meek, Mem. Am. Acad. V, new 



ser. I, fig. 7. 



432 = Cytherea Owenana, Meek & Hayden, Proc. Acad. Nat. Sci. 



VIll, 273. 



433 = Cytherea pellucida, Meek & Hayden, ib. Nov. 1856, 278. 



434 = Cytherea texana, Conrad, Mex. Bound. Rept. I, part 2, 1858, 153, 



vi, 2. 



435 = Cytherea tippana, Conrad, Jour. Acad. Nat. Sci. VIII, sec, ser. 



326, xxxiv, 18. 



436 = Venus Meekiana, Gabb, ib. IV, 394, Ixviii, 23. 



437 = Venus ripleyana, Gabb, ib. 393, Ixviii, 22. 



3 



