430 American Seashells 



Compare with lintea which lacks the dorsal crenulations. Formerly placed 

 in the genus Tellina. 



Genus Quadrans Bertin 1878 

 Quadrans lintea Conrad Lintea Tellin 



Figure 86g 



North Carolina to both sides of Florida and the West Indies. 



% to I inch in length, moderately oval, slightly inflated, quite strong 

 and all white in color. Posterior dorsal slope with 2 radial ridges in the 

 right valve, i in the left. Concentric lamellae numerous, sharp and minutely 

 raised. Left valve with 2 extremely weak, long laterals, but these are well- 

 developed in the right valve. Dorsal line of the palhal sinus meets the pallial 

 line not far from the anterior muscle scar. Posterior twist to the right is 

 fairly pronounced. Commonly dredged off the Carolinas (9 to 16 fathoms), 

 uncommonly found in a few feet of water on the west coast of Florida, 

 Formerly placed in Tellina. 



Genus Tellidora H. and A. Adams 1856 

 Tellidora cristata Recluz White Crested Tellin 



Plate 30-0 



North Carolina to west Florida and Texas. 



I to 1/4 inches in length, roughly ovate, compressed and all white. 

 The left valve is very flat, the right valve slightly inflated. Dorsal margins 

 of valves with large, saw-tooth crenulations. A bizarre clam found un- 

 commonly in shallow water. 



Genus Macoma Leach 18 19 



The Macomas are modified tellins which may be distinguished by (i) 

 no lateral teeth; (2) usually dingy-white in color and of a chalky consistency; 

 (3) there is a strong posterior twist; (4) the pallial sinus is larger in one valve 

 than the other. 



Macoma calcarea Gmelin Chalky Aiacoma 



Figure 88f 



Greenland to Long Island, New York. Bering Sea to off Monterey, 

 California. 



1% to 2 inches in length. Oval-elongate, moderately compressed, but 

 somewhat inflated at the larger, anterior half. Beaks % the way toward 

 the narrowed, slightly twisted posterior end. Shell dull, chalky-white. Con- 



i 



