79 
or yellowish ray; somewhat violet within, hinge with 
two teeth in each valve, and a single lateral one. 7...14. 
Torbay and Guernsey. 
D. Ruspra. Mont. Sup. p. 38.—Turt. C. D. p. 43. 
—Turt. B. p. 127. t. 10. f. 14.—F. p. 485.— W edge- 
shaped, smooth, uniform pale claret color, posterior 
edge greatly sloping to an attenuated but rounded ex- 
tremity, glossy, semi-transparent; beaks prominent, 
posterior ; a single approximate lateral tooth in eaeh 
valve. 3. Tenby. 
GENus.—CRASSINA,. 
Suborbicular, transverse, equivalve, subinequilateral, 
close; hinge with two strong diverging cardinal 
teethin the right valve, and two unequal ones in the 
other ; ligament external, broader than long. 
* Margin quite entire. 
C. Scorica. Turt. B. p. 130. t. 11. f. 3,4.—VeEnus 
S. Mont. Sup. p. 44.—Lin, T. 8. p. 81. t. 2. f. 3.— 
Pen. 4. p, 204.—D. p. 267.—Turt. C.D. p, 236.— 
AsTarteE 8. -F. p. 440,—Rounded-heart-shaped, rather 
flat, white, under an olive or chesnut cuticle, very 
