167 



opaque, ferruginous, or dull purple. T\Iargin fcolloped, 

 or cut into deep, irregular notches, on both valves, cor- 

 refponding with e^.ch other, fo as to be inferted, and 

 fliut clofe, Infide white, or tinned with fcrrusjinous : be- 

 neath the hinge, in the fuperior valve, (lightly crenulated. 

 Diameter two inches and a half. 



This fpecies, though as yet not afcertained to breed in 

 this climate, has been found alive adheringr to the bottom 

 of fliips ; and pofiTibly may become naturalized, as well 

 as the Feredo navalis, which was firfl introduced in the 

 fame manner, and now become formidable in fome of 

 our harbours. 



Is common in India, and in the Red Sea, 



10. 

 Mytilus difcors. Lin. Syft. p. 1159.— GmeL Syji. p. S356. 21. DiscoR: 

 C/iem. Conch, viii. t. S6. f. 764. 767. 

 T»a. Cojla. p. 2211. t. 17. f. 1. 

 Walk. Min. Shells, f. 79. 

 Adams. Micr. t. 14. f. 41. 

 Puh. Cat. Dorfet. p. 38. 

 Don. Br. Shells. i.t.2b.—Turt. Z/«.iv.p.294. 



M. with a very convex, fub-cordated, pellucid fliell ; 

 the pofterior and anterior fides longitudinally ribbed or 

 flriated, broader and ftroncrer on the former : the mid- 

 die area is plain, or faintly wrinkled iranfverfely : umbo 

 large, prominent; apex turned much to one fide, and 



placed 



