CARDIIDAE 401 



Exterior orange-yellow; interior china-white. This is the largest species of 

 recent cockles and is moderately common. 



Genus Dinocardium Dall 1900 

 Dinocardiu77t robustum Solander Giant Atlantic Cockle 



Plate 32a 



Virginia to north Florida, Texas and Mexico. 



3 to 4 inches in size, ovate, inflated, with 32 to 36 rounded, radial, 

 smoothish ribs. Externally straw-yellow with its posterior slope mahogany- 

 red shading toward purple near the edge. Interior rose, with brownish 

 posteriorly and with a white anterior margin. This is the large, common 

 cockle washed ashore along the Carolina and Georgia strands. It is not found 

 in southwest Florida. 



When the Florida Canal project was begun in 1935, President F. D. 

 Roosevelt was presented with a large silver platter on which was set a 

 specimen of Di7iocardium, encased in gold and containing a portion of the 

 first earth excavated as a result of the blast set off by the President. The 

 canal was never completed. 



Dinocardium robustwit vanhyningi Clench and L. C. Smith 



Vanhyning's Cockle 



Plate 32b 



Tampa Bay to Cape Sable, Florida. 



3% to 5 inches in size, higher than long, with 32 to 36, smoothish, 

 rounded, radial ribs. Externally straw-yellow with irregular patches and 

 bands of mahogany-red to purplish brown. It is more elongate, glossier and 

 more colorful than robustum, and is the common, large cockle on the west 

 coast of Florida. They are popular souvenirs, being used for ash trays, 

 melted-butter dishes, baking dishes and for holding pincushions. 



Genus Serripes Gould 1841 



There is only one species of this peculiar genus of cockles in North 

 American waters. The hinge is narrow, the cardinal teeth weak, and the 

 ligament is large. The radial ribs are very weak. 



Serripes groenlandiczis Bruguiere Greenland Cockle 



Plate 32d 



Arctic Seas to Cape Cod, Massachusetts. Alaska to Puget Sound, Wash- 

 ington. 



2 to 4 inches in length, moderately thin bur strong, inflated, almost 



