

402 tellininjE. 



Genus GASTRANA, Schumacher. 



Shell sub-equivalve, inequilateral, both valves convex; 

 surface more or less striated or ridged tranversely, not in- 

 vested with an epidermis. Hinge composed of two primary 

 teeth in one valve, and one bifid tooth in the other; no 

 lateral teeth; ligament external. Muscular and pallial 

 impressions strongly marked, the former oblong and nearly 

 equal, the latter with a very deep and wide sinus. 



Si/n. Capsa, part, Brug. Diodonta, Desk. Fragilia, 

 Desk. 



Ex. G. fragilis, Linnaeus, pi. 104, fig. 4. Shell. G. 

 fragilis, fig. 4, a, 4, b. 



In this genus the mantle is open, the margins are fimbri- 

 ated, and the siphons arc separated to their bases ; the gills 

 are unequal, and the labial palps large and triangular. The 

 species inhabit shallow water, boring in mud and clay, and 

 not travelling about like the Tellens. They are found at the 

 Cape, in Senegal, the Black Sea, Britain, Greenland, and 

 the Mediterranean. 



Species of Gastrana. 



angulata, Linn. inflata, Desk. 



fragilis, Linn. polygona, Chent. 



Guinaica, Chem. ventricosa, Krauss. 



Genus LUCINOPSIS, Forbes and Hanley. 



Mantle-margins plain; pedal opening contracted; foot 

 pointed, basal. 



Shell rather thin, compressed; valves with the inner 



