1856.] 



Gen. BUCCINUM. 

 B.? viNCCLDM, Hall & Meek, Mem. Am. Ac. Art. & Sc. Bost., v. 5, N. S. p. 390 



B. cONSTRiCTUM, Hall & Meek, " " " p. 391 



(See correction at end of that memoir.) 



B.? Nebbascensis, Meek & Hayden, Proc. Acad. Nat. Sci. Phila., v. 8, p. 67 



Gen. CAPULUS. 



C. occiDENTALis, Hall & Meek, Mem. Acad. Art. & Sc. , vol. 5, N. Ser. p. 385 

 C. FBAGILI3, Meek & Hayden, Proc. Acad. Nat. Sci. Phila., vol. 8, p. 68 



283 



Formations in 



ascending order. 



12 3 4 5 



It 



(< 





(I 

 a 

 ti 

 u 



Gen. HELCION 



H. BOREALiS, Morton sp 



Hipponyx borealis, Morton, Jour. Acad. Nat. Sc, Phila., v. 8, pi. 11, fig. 6 

 H. SExsuiiCATUS, Meek & Hayden, Proc. Acad. Nat Sci. Phila., vol. 8, p. 68 

 H. PATELLiFORMis, Meek & Hayden, 

 H. ALVEOLis, Meek & Hayden 

 H. suBovATus, Meek & Hayden, 

 H. CAEINATUS, Meek & Hayden, 



Gen. DENTALIUM. 



D. GRACILIS, Hall & Meek, Mem. Am. Ac. Art. & Sci. Bost., v. 5, N. S. p. 393 

 D. PBAGiLis, Meek & Hayden, Proc. Acad. Nat. Sci, Phila., vol. 8, p. 69... 



Gen. BULLA. 

 B. VOLVARIA, Meek & Hayden, Proc. Acad. Nat. Sci. Phila., vol. 8, p. 69, 

 B. MINOR, Meek & Hayden, " " " " 



B. OCCIDENTALIS, Meek & Hayden, " " " " 



B. suBCYLiNDEicA, Meek & Hayden, accompanying paper. " 



Gen, PHALODOMYA, 



P. ELEGANTULA, Evans & Shumard, Proc. Acad. Nat. Sc. Phila., v. 7, p. 164 



P. (Goniomya) Americana 



Goniomya Americana, Proc. Acad. Nat. Sci. Phila., vol. 8, p, 8 



P. UNDATA, Meek & Hayden, " " " v, 8,p. 81 



P. FIBROSA,* 



.4t;8cwZa.?/6rosa, Meek & Hayden, " " " v. 8, p. 86 



Gen. PAN OPE A, 

 P. OCCIDENTALIS, Meek & Hayden, (acompanying paper) 



Gen. SOLEMYA. 



S. SUBPLICATA, 



Sokn subplicata, Meek & Hayden, Proc. Ac. Nat. Sci. Phila., vol. 8, p. 82 



Gen. MACTRA. 



M. FORMOSA, Meek & Hayden, (accompanying paper).. 

 M, Warrenana, Meek & Hayden, 

 M. ALTA, Meek & Hayden, 



If 

 ti 





* This species, of which we only had imperfect specimens, we had referred with much 

 doubt to the genus Avicula, mentioning at the same time that we had not seen any 

 specimens showing indications of an anterior wing. Recently we have been informed 

 by Dr. Shumard, who has better specimens of it in his possession, belonging to the 

 collection of Dr. Evans, that it is a Pholodomya; consequently we place it in that 

 genus on his authority 



