101 
straight, without ribs at the extremities ; teeth nu- 
merous, serrated, close-set, alternately inserted into 
opposite valves ; ligament external. 
* Crenulated at the margin. 
_ A. Now. Inn. 1140.—D. p. 226.—Lam. 3.—Ch. f. 
529.—Mont. p. 139.—Pen. 4. p. 215.—Lin. T. §. p. 
91.—Don. 5. ¢.158. f. 1,2.—Turt. D. p. 9. f. 58.— 
Turt. B. p. 166.—F. p. 597.—Oblong, decussated in 
a punctured manner, pale rufous with darker oblique 
bands, rounded posteriorly, anteriorly angular; beaks ; 
nearone end, very remote, incurved, with a broad smooth 
space between them ; ventral edge sinuous and gaping 
in the middle; inside whitish or pale chocolate brown. 
1 
2...4. Guernsey and W. Coasts. 
A. Fusca. Don. 5. t. 158. f. 34.—Mont. Sup. p. 
51. ¢. 4. f.3.—Pen. 4. p. 215.—Turt. D. p. 10.— 
Turt. B. p. 167.—F. p. 397.—Impricata. D, p. 
226.—Ch. f. 532,—List. ¢. 367. f. 207.—Oblong, 
uniform brownish white, decussated, angular anteriorly, 
the ventral edge shorter, straight and nearly closed. 
W. Coasts.—Resembling the last, but is proportionably 
narrower, more convex, with finer decussations, the 
margin nearly straight and the beaks very remote.. 
Rare. 
