TRIBE NYMPHACEA. 63 



longer and having an angular slope separated in the convex valve by 

 an elevated ridge, and by a corresponding depression in the other : 

 hinge with two cardinal teeth (one cleft) in the convex, a single tooth 

 in the flatter valve : no lateral teeth, 1^..2|-. — South America? 

 — East Indies. 



T. Rosea. Lam. 14. Ovate-triangular, rather convex, pink, 

 becoming darker at the beaks and interior, very indistinctly decus- 

 sated. 2 . . 3. — California. 



T. Elliptica. Lam. 16. Oblong-elHptic, very finely striated, 

 thin, whitish with the beaks purplish, and slightly tinged with 

 orange, but more so in one valve than the other : orange within. 3. 



T. Margaritina. Lam. 18. — Del. t. 6.f. 4, Oval, attenu- 

 ated and longer anteriorly, thin, pellucid, polished white ; inside 

 slightly pearly. ^ — Neyv Holland. 



T. Albinella. Latn.17. Ovate-oblong, very flat, thin, pellucid 

 whitish, with the beaks indistinctly horn-coloured : anterior side 

 attenuated and sub-angulated. \^. — Hew Holland. 



T. Strigosa. Gmel. 3239.— i>. p. 82.— Lam. \9.—Adans. 

 t. \7. f. 19.— TP^. t. A. f. 61. Ovate-oblong, sub-equilateral, 

 anteriorly attenuated and sub-rostrated, posteriorly rounded, rather 

 flat, sub striated transversely, white within and without, with 

 lateral indistinct greyish or yellowish bands : hinge with not more 

 than a single tooth. 2i. — W. Africa. 



T. Planata. Lin. U\7.—Lam. 20.— D. p. 81.— TF. t. 3./. 

 24.— T. CoMPLANATA. Gmel. 3239 —Poli. I. t. 14./. \ to 15. 

 —Born. t. 2. f. d.—An. var.? Ch. f. 98. Ovate, sub-equi- 

 lateral, anterior side ventrally sub-angulated, sub-striated trans- 

 versely, reddish fulvous at the beaks, and interior, elsewhere whitish 

 tinged with the same colour : a bifid and simple cardinal tooth in 

 one valve, a bifid one in the other, no distant lateral ones. ^..2^. — 

 M edit err anean.- 



T. PuNiCEA. Gmel. 3239.~(T. Angulosa. Gmel. 3244.)— 

 J>. p. 90.— Lam. 21.— Born. t. 2. f. 2.— E. t. 291. /. 2.— T. 

 Striata. Ch.f. 1654, 5.— Dorset. Cat. l.f. 5.— TF. t. 4./. 64. 

 Elongated-oval, sub-inequilateral, slightly angulated and inflected at 

 the shorter anterior end, rather thin, crimson, varying in depth and 

 often with paler unequal bands, deeply and regularly striated trans- 

 versely ; cardinal teeth cleft ; with lateral ones. — Variety. White. 

 — -jL. . 1^^^. — Mediterranean. 



T. Depressa.* Lam. 22.— W. t. 4. /. 48. — Gmel. 3238.— 

 Turt. Biv.t. 8. f. 6.— Don. 5. t. \63.—Gualt. t. 88. L.—T. In- 



2 We have given a copy of the T. Flavescens, Ch.f. 98. — (W. 

 t. 4. f. 88.) which Mr. Deshayes considers as a variety of this 

 species. 



