42 



8.^>. 36. Dor. Cat. p. 27. t. 4. /. 6. Wood. G. C. 

 p. 93. t. 18. /. 3. A. MYALIS. Lam. 9. THRACIA. 

 P. Kiener t. 2.f. 2. Oblong, depressed, angular and 

 truncate anteriorly,rough, striated transversely, brownish 

 white ; beaks nearly central, the points crossing each 

 other at the tips ; teeth projecting and running obliquely 

 to the anterior side with a cavity or notch behind and 

 small erect denticle inside, with an oblique rib from the 

 tooth towards the truncated end. Torbay and Ply- 

 mouth. 2i...3i. 



A.TRUNCATA. Turt. B.p.W. t. 4./. 6. AMPHI- 

 DESMA. T. F. p. 431. Convex, wedge-shaped, poste- 

 riorly very short and obliquely subtruncated, anteriorly 

 attenuated and truncated ; rough, striated transversely, 

 dirty white; teeth projecting a little inwards but run- 

 ning obliquely (thus distinguished from Distorta,) 

 front margin forming nearly a straight line, i....|. 

 In rocks, Torbay. 



* * Teeth projecting horizontally inwards. 



A. DECLIVIS. Turt. B. p. 47. MYA. D. Mont. t. 

 I./. 2. AMPHIDESMA. D. F. p. 432. Oval-oblong, 

 slightly compressed, angular truncated and open an- 

 teriorly, white, minutely shagreened, posteriorly broad 

 and rounded. 1....H. Torbay. Distinguished from 



