concave tooth and small denticle behind it ; no late- 



ral teeth : ligament internal. 



S. BINGHAMI. Turt. B. p. 36. t. 3./. 4, 5. $ t. 19. 

 /. 3. F. p. 465. Wedge-shaped, covered with a brown 

 wrinkled skin which extends beyond the anterior end, 

 truncate at the hinge, with the upper margin often a 

 little contracted about the middle, gradually tapering to 

 the open anterior extremity ; beaks rather prominent, 

 with the points not quite opposite but diverging from 

 each other ; in>ide glossy white with a purplish tint, the 

 margin short and plain, the concave tooth oblique and 

 inflected . . . . . i . Torbay, in rocks. 



S. SWAINSONI. Turt. B.p. 37. t. 3./ 3. and t. 19. 

 f. 2. F. p. 466. Oval, wedge-shaped, rounded ante- 

 riorly ; the concave tooth projecting horizontally 

 inwards. \ . . . ih Torbay, in rocks. 



GENUS. PANDORA, 



Regular, inequivalve, inequilateral, and transversely 

 oblong; upper valve flattened, under convex ; hinge 

 with two oblong diverging cardinal teeth in the 

 upper valve ; the other valve with two corres- 

 ponding grooves : ligament external. 

 \\ OBTUSA. Lam. 2. Sow. Sp. Con. /. 1, 2, 3. 

 SOLEN PINNA. Mont. t. 15. /. 3. Ovate, pos- 

 terior side very short, obtuse and olliquely rounded at 



