~I 
~T 
—Cyruerea T, Lam. 53.—Turt. B. p. 164, €. 12. 
f. 12.—F. p. 445.—Orbicular, compressed, white, 
with longitudinal ribs which are rather flat, very close, 
numerous, and narrow, and are crossed by still closer 
set concentric wrinkles; lunule minute, triangular, 
sunken; ligament buried; inside white, often tinged 
with rose-color about the hinge and margin; palleal 
scar simple, two cardinal teeth in each valve, a lateral 
in one, its receptacle in the other. 1. Guernsey. 
Grnus.—DONAX, 
Transverse, equivalve, inequilateral, anteriorly very 
short and obtuse; two cardinal teeth in one or 
both valves, and one or two lateral teeth more or less 
apart ; ligament external. short. 
* Inner margin erenulated. 
VD. Anatinum. Lam. BI. t.71.f. 2—D. Truneov- 
ius. D. p. 150.—(not Lin. nor Lam. 24.)—List. 
¢t. 376. f. 217.—Da Cos. t. 14. f. 3.—Pen. 4. p. 98. 
t. 55.—Mont. p. 103.—Turt. B. p. 123.—Lin. T. 8. 
p. 74.—Dor. Cat. p.33.t. 6. f.3.—Don. t. 29. f. 1, 
—Turt. C. D, p. 4\.—F. p. 433.—Oblong wedge- 
shaped, the hinge margin nearly straight, glossy, with 
numerous simple minute radiating strie, except at the 
