77 



CYTHEREA T. Lam. 53. Turt. E. p. 164. t. 12. 

 /. 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. 



GENUS. 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 crenulated. 



D. ANATINUM. Lam. Bl. t. 71. f. 2 D. TRUNCU- 

 LUS. D. p. 150. (not Lin. nor Lam. 24.) List. 

 t. 376. /. 217. Da Cos. t. 14. /. Z.Pen. 4. p. 93. 

 t. 55. Mont. p. I03.Turt. B.p. 123. Lin. T. 8. 

 p. 74. Dor. Cat. p. 33. t. 6. /. 3. Don. t. 29. /. U 

 Turt. C.D. p. 41. F. p. 433. Oblong wedge- 

 shaped, the hinge margin nearly straight, glossy, with 

 numerous simple minute radiating strise, except at the 



