6$ TESTACEOUS MOLLUSCA. 



Sub-orbicular, slightly convex, white, with the beaks smooth and 

 the rest of the surface covered with transverse undulated ridges, 

 rather inflected and angulated on the anterior side : hinge with two 

 teeth in one valve and one in the other, besides two strong lateral 

 teeth of which the anterior one is much more remote. — Variety, 

 with obsolete rufous bands. Diam. 2\. — India. 



* T. Crassa. Pennant. 4. t. 48. /". 28.— Gmel. 3288. -D. p. 

 96.— E. t. 291. /. 5.— IF. t. 4. f. 7d.— Lam. 35.— List. t. 299. 

 f. 136. — Turt. Bio. t. 7- f. 2. — Roundish, thick, heavy, semi- 

 transparent, with one valve less convex than the other, anteriorly 

 shorter ; white or yellowish, (with usually reddish rays,) crowded 

 with transverse furrows which are coarser posteriorly, the beaks 

 frequently stained with pink, within yellowish, a simple and bifid 

 tooth in each valve besides two lateral teeth in one of the valves. 

 1 J . . 2. — Europe. 1 



T. Fausta. Dil p. 94.— T. Remies. Lam. 31.— Born. t. 2. 

 f. 11.— List. t. 266. f. 102. — Ch. f. \\2.—E.t. 290. /. 2 — 

 T. LiEvis. Wood. G. C. t. 37. f. l.—W. t. 4. f. 68. Roundish 

 ovate, posteriorly slightly longer and rounded, anterior edge sloping, 

 anterior side slightly inflected and obtusely truncated at the tip : 

 white, strong, finely but regularly striated transversely, but smooth 

 at the beaks, marked with anastomosing fine interrupted radiating 

 lines, ventral edge arcuated : inside tinged with yellow, a cleft and 

 a narrow simple cardinal tooth in one valve, the latter scarcely 

 rudimentary in the other, a distant and an approximated lateral in 

 each. 2 . . 2§.— W. Indies* 



T. Scobinata. Lin. 1119.— D. p. 98.— Lam. 34.— List. t. 

 302. f. 143.— F. t. 291./. 4.— Ch. f. 122, 3, 4.— Reeve, t. 55. /. 

 2.—So?v. G.— W. t. 7. f. 67.— Wood. G. C. t. 35. /. 1. Sub- 

 orbicular, slightly inflected and angular anteriorly, whitish, rough- 

 ened with lunate scales disposed in quineunxes and enlarged in 

 size as they recede from the beaks, and usually with a few brown 

 or ferruginous scattered spots, sometimes forming rays ; hinge 

 central, with bifid cardinal teeth and strong lateral ones in each 

 valve. Diameter up to 3f.— Indian Ocean. 



T. Levigata. Lin. p. 103.— D. p. 82.— Lam. 36.— Ch. f. 

 111.— Wood. G. C. t. 41. /. l.—W. t. 4. f. 29.— Roundish- 

 ovate, with concentric striae becoming obsolete on the disc, whitish 

 with tawny orange rays and the ventral margin tinged with the 



1 When the minute longitudinal striae in the interstices are more 

 evident, and the rays absent, it forms the Reticulata of British 

 authors, but not of Linnaeus. 



2 Striatularts, Lam. 33, is apparently a young shell with the 

 rudimentary tooth quite obsolete. 



