Ill 



GJJNXJS. LITHODOiMUS. CUVIER, 

 Subcylindrical, rounded at both ends; beaks nearly 



terminal ; no teeth ; ligament al line nearly straight. 



L. LITHOPHAGUS. Lin. 1156. Lin. T. 8. p. 270, 

 t. 6./. 1. to 5. -Cuticle green, finely striated by the 

 layers of growth ; inside glossy, irridescent. 0,40... L 

 Limestone, very rare. 



GENUS. PINNA. 

 Longitudinal, equivalve, cunieform, acute at the beaks, 



gaping at the opposite extremity ; beaks straight ; 



hinge lateral and toothless; ligament marginal t 



linear f very long, almost internal. 



P. INGENS. Pen. 4. p. 115. Mont. p. 180. Lam. 

 \3.Mont.p. ISO.F.p. 406. P. L^vis. t. 152. 

 P. INGENS. & FRAGILIS. Turt. B.p. 222. t. 22. /. 

 1. Oval-triangular, semitransparent, horn coloured, 

 with concentric arched striae, a few longitudinal obsolete 

 ridges towards the back ; ligamental edge straight, com- 

 pressed anteriorly, from whence it runs almost directly 

 for two-thirds and then slopes suddenly to the beaks. 

 6... 12. S. Coasts, deep water. 



P. FRAGIMS. Pen. 4. p. 114. t. 69. /. 80. P.p. 

 406. P. MURICATA.DO?J. 1. 10. PECTINATA. Mont, 

 p. 178,TurL B. p. 223. t. 19. /. 1 .Triangular, 



