OF COXCnOLOGY. 71 



NOTES ON RECENT AND FOSSIL SHELLS, WITH DE- 

 SCRIPTIONS OF NEW SPECIES. 



BY T. A. CONRAD. 



MACOMA Leach. 

 M. SUBROSEA. PI. 1, fig. 3. 



Description. — Subtriangular, equilateral, convex ; substance 

 very thin ; beaks slightly prominent, direct; posterior side cunei- 

 form; ventral margin rounded, disk minutely striated concen- 

 trically, white and glossy, with a thin, pale ochreous periostraca ; 

 cardinal tooth in the left valve compressed, with a minute linear 

 sulcus. 



Locality. — Raritan Bay, near South Amboy ; Delaware Ba;/. 



This delicate shell was found amonoj the sea weed cast ashore, 

 and all the specimens were dead shells, but with the valves con- 

 nected by a strong elastic ligament. The shell is more elevated, 

 triangular and equilateral than any other of the small American 

 species. 



It has some resemblance in outline to Macoma fusca, Say, 

 which accompanies it, but can readily be distinguished by its 

 smaller size, more prominent beaks, shiny and iridescent valves, 

 flexuous posterior side, &c. Specimens from Delaware Bay are 

 larger and rosaceous. 



CYCLOCARDIA. 



Prof. Morse, in the Peabody Acad. Report, makes this genus 

 a subgenus under Actinobolus, Klein, the type of which is Circe 

 pectinata. Its nearest affinity is Venericardia, Lam. 



CAPULUS, Moiitf. 



C. Shreevei, Amer. Journ. Conch., Vol. V, pi. 13, fig. 3. 



This supposed species proves to be a tooth of Pholas costata. 

 It has a tubular character towards the upper end, which is con- 



