42 PALEONTOLOGY OF NEW JEESEY. 



ANOMIID^. 



Genus AjSTOMIA Liun. 

 Anomia argentaria. 

 Plate IV, Figs. 9-11. 



Anomia argentaria Morton. Synopsis, p. 61, PI. V, Fig. ]0. Gabb, Synopsis, p. 94. 



Meek, Check-list, p. 6. Geol. Surv. N. J., 1868, p. 724. Gabb, P. A. K 



Sci., 1876, p. 319. 

 Comp. A. micronema Meek. Bull. U. S. Geol. Surv., 2d ser., No. 1, p. 43, 1875. Con- 



trib. to Pal. Dept. Interior, No. 4, p. 57, PI. XXV, Fig. 2. 

 Comp. A. f ohliqua M. & H. Invert. Pal. Territ., p. 22, PI. IX, Fig. 2. 



Shell small, thin, irregularly circular, and moderately convex on the 

 deep valve. Surface marked by closely arranged, regular concentric lines, 

 at almost regularly increasing distances, and by very fine, hair-like, regu- 

 lar, radiating lines or striae, which are interrupted at the concentric lines. 

 Surface of the shell nacreous, having a silvery white luster. Pei'forated 

 valve not observed. 



The shell used in the above description is the only one I have seen at 

 all approaching that described by Dr. Morton, in the regularity of the con- 

 centric lines. The shell is not as regular in outhne as his figure, and he 

 says nothing about the fine radiating striae seen on this specimen. As com- 

 pared with shells of A. teUinoides, its outline is not more regular, but the 

 apex is situated within the margin of the valve, not being marginal or pro- 

 jecting as in that one, and the regularity of the concentric striae and the 

 fine radii are certainly distinguishing features. In Kerr's Report Geology 

 North Carolina, Appendix, page 1 3, Mr. Conrad cites A. argentaria and A. 

 teUinoides as synonyms. I may be in error in considering this shell as iden- 

 tical with Morton's A. argentaria, but if not, I certainly should consider it 

 as distinct from A. teUinoides. It bears a striking resemblance to Anomia 

 micronema Meek, from the Laramie Group of the west in its general form 

 and in the radiating lines of the surface, and seems almost too nearly like it 

 to be considered distinct, although of a diff'erent geological horizon. 



Formation and locality. — In the lower bed of the Lower Green Sand at 

 Freehold, New Jersey. 



