O. EDULIS. Lin. 1 148. Pen. 4. p. 225. /. 65. /. 2. 

 Mont. p. 151. Dor. Cat. p. 38. *. 11. /. 6. D. 

 ^. 280. TV*. D.^. 133. Lam. I. List. t. 193. /. 

 30. Ch.f. 682. Da Cost. t. 2./. 6: Blain. t. 60. 

 /. l.E.t. 184. /. 7,8. jF.^. 392. Rounded-oval, 

 rather attenuated towards the beaks, dirty white, rough, 

 with concentric waved scaly foliations; upper valve less 

 and flattened ; inner margin very entire. The common 

 Oyster. 



O. PARASITICA. Turt. B.p. 205. t. 17. /. 6,7. F 

 p. 392. Turt. D.p. 134. /. 8. Rounded or oblong, 

 nearly smooth, the upper valve convex, greenish, often 

 with radiating bands of brown. If. Attached to 

 marine substances. Probably a variety ofEdulis and 

 deriving both form and color from the Pectens, fyc. it 

 may have attached itself to. 



GENUS. ANOMIA. 



Inequivalve, irregular ; with the under valve perfora- 

 ted near the beak and fixed by an operculum or 

 tendon ; hinge withont teeth ; ligament internal, 

 placed transversely under the beak. 

 A. ELECTRICA. Lin. \l5I.-Turt.D.p. I./. 67. 

 Turt. B. p. 227. t. 17. /. 8,9.^.^ 394. Some- 

 what orbicular, with the surface a litle undulated, bright, 



