CHAMA. 219 



rugosa. 13. Shell sub-orbicular, with very deep 

 grooves, and slightly imbricated wrinkles ; 

 margin doubly plaited. 



Chama rugosa. Linnccus Mant. p. 546. Gmelin, p. S305. 



Inhabits 



Linnaeus describes this shell to be " as large as the last joint 

 of a ringer, gibbous, thick and white, with thirty deep pa- 

 rallel grooves ; wrinkles compressed, and on the back slight- 

 ly imbricated ; scales rather obsolete, distant, and numerous ; 

 inner margin obtuse and plaited, and the outer set with pro- 

 jecting concave scales proceeding from the wrinkles ; hinge 

 with two or three oblique grooves, declining towards the 

 anterior side." Linnaaus in the Mantissa, has described 

 another Chama, with the name of C. gryphica, which he 

 says is found in Barbary, and it therefore appears to be a 

 fossil species. 



oblonga. 14. Shell ovate-oblong, with delicate 

 decussated striae, and the anterior side ob- 

 liquely keeled ; inside yellowish. 



Chama oblonga. Linnaus Syst. Nat. p. 1139- Schroeter 

 Einl. iii. p. 241. Gmelin, p. 3302. Chemnitz, xi. p. 

 238. t 203. f. 1993 and 1994. 

 Chama Guinaica. Chemnitz, vii. p. 137. t. 50. f. 504 and 



505. 

 Cardita carinata. Bruguiere Enc. Meth. p. 409. 

 Enc. Meth. t. 234. f. 2. 

 Inhabits the coasts of Guinea. Chemnitz. Pulo Condore. 



Humphreys. 

 Shell about sixteen lines long, and nine broad, white, some- 

 what pellucid, and the inside yellowish, and sometimes 

 stained with purple ; it is marked with fine longitudinal stria?, 

 which are crossed transversely by others still more minute, 

 and an elevated keel extends from the summit obliquely, to 

 the posterior angle of the margin. In form it bears some 

 resemblance to Mytilus modiolus. 



concamerata. 15. Shell ovate-oblong, longitudi- 

 nally ribbed, and transversely wrinkled, with 

 a separate chamber formed at the middle of 

 the inner margin. 



Chama concamerata. Chemnitz, vii. p. 138. t. 50. f. 506. 

 Gmelin, p. 3304. 



