21 



Totteu Informs me, the species is very rare. It is 

 also scarce upon the southern shores, where it was 

 first observed by Mr. Say. It inhabits the coast of 

 Great Britain and is probably one of the rarest bi- 

 valves of that Island. 



SOLECURTUS COSTATUS. 

 Tab. IV, fig, 2. 



SPECIFIC CHARACTER. 



Shell oval elongated, much compressed, very thin 

 and fragile, with an internal rib descending nearly 

 perpendicular from the beak, expanding and becom- 

 ing obsolete near the basal margin. 



SYNONYMA. 



SoLECURTUs cosTATUs. Say, American Conch. pL 



18. 

 SoLEN COSTATUS. Say, Journ. Acad. JVat. Scie?2' 



ces, vol. 2, p. 313. 



Cabinet of the Acad. Nat. Sciences, No. 1214. 



OBSERVATIONS. 



The colour is violaceous, with two or three pale 

 rays ; the epidermis is polished and olive vellow on 

 the inferior half of the shell, and a flesh coloured 



C 



