22 



whose base is affixed to marine substances. Mouth 

 almost inferior. 



GENUS ANATIFA. 



Compressed at the sides, composed of five valves, which 

 are contiguous and unequal, the lower lateral ones 

 being the larger. 



A. L^vis. Lam. 1. Philippi. p. 252. Bmg. p. 

 62. LEPAS ANATIFERA. Lin. 1109. D. p. 32. 

 Ch.f. 852. Don. t. 7. Dor. Cat. p. 26. t. 2. /. 3. 

 Mont. p. 15. Wood. G. C. t. \\.-Knorr. 2. t. 

 30. /. 4. 6.Turt. D. p. 71. PENTELASMIS A. 

 Leach. Reeve, t. 12. P. LJEVIS. Bl. t. 84. /. 3. 

 Compressed, polished, and bluish white ; the two lower 

 valves large and somewhat triangular, longitudinally 

 wrinkled and obsoletely striated radiatingly from the 

 lower anterior angle : the two upper valves angulated 

 on each side, top rounded, (these likewise are nearly 

 smooth) ; dorsal valve long, slender, rounded, smooth 

 down the middle and sulcated on each side ; membrane 

 and peduncle usually reddish. Length of shelly part, 

 1&...1. On ship's timber, common. 



A. STRIATA. Lam. 4. Philippi. p. 252. Brug. 

 p. 64. LEPAS ANSERIFERA ? Lin. 1109. D.p. 31. 

 List. t. 440. /. 283. Ch. f. 856. Don. t. 162. 

 /. 2. Mont. p. \7.-Turt. D.p. 72. Much resem- 



