107 



short ; beaks almost lateral, inclining to the shorter 

 side ; hinge toothless, lateral, linear ; cartilage sub- 

 internal, situated in a marginal groove / scar single, 

 sublateral, elongated and hatchet-shaped. 



M. RHOMBKA. Berkely in Z. J. 3. p. 229. t. 18. /. 

 1. 'Thin, rhombic, gibbous, with transverse subcrenu- 

 lated folds which are posteriorly obscure, and longitu- 

 dinal ribs ; uinbones incurved, slightly prominent. 

 Length 0,17. Weymouth, rare. 



M. MODIOLUS. Turt. B.p. 199. t. 15./. 3. ARCA 

 M. Lin. \L5S.-Pen. 4. p. 238. t. 69. Da Cos. p. 

 219. t. \5.f. 6. Don. 1. t. 23. Lin. T. 8. p. 107. 

 Dor. Cat. p. 40. t. 12. f. 5.D.p. 314. Turt. D. 

 p.l\\.E.t.2l9.f. ]. M. VULGARIS, F.p. 412. 

 Oblong, smooth, long, thick, coarse, covered with a 

 blackish skin, anteriorly obliquely dilated, the beaks 

 tumid and obtusely angular ; when half grown thinner, 

 of a horn color and usually clothed more or less with 

 long leaf-like filaments which are entire on both their 

 edges. (M. BARBATUS. Lin. 1156. Ch. f. 749. 

 Pen. 4. p. 238. t. 67. /. 2. Don. 2. t. 70.) 4 or 5. 

 Common. 



M. GIBBSII. Turt. B.p. 2QO.F.p. 4\3.Leack, 



