THRACIA. 221 



T. PHASEOLiNA, LaiTiarck. 



Small, white, oblong, rather oblique, more or less glossy, 

 smooth, except posteriorly ; anterior side the longer ; posterior 

 termination subtruncated : ossicle broader in the middle. 



Plate XVII. fig. 5, 6, and (animal) Plate H, fig. 4. 



Tellinafmgilisf Penn. Brit. Zool. ed. 4, pi. 47, f. 25. 



Mya declivis, Turt. Conch. Diction, p. 98. — Index Testae, pi. 2, Mya, f. 4. 

 „ „ young. Wood, General Conch, pi. 18, f. 3. 



„ pubescens, young, Turt. Dithyra Brit. pi. 4, f. .3. 

 Anatina declivis, TuRT. Dithyra Brit. p. 47. — Brit. Marine Conch, p. 42. 

 Amphidesma declivis, Flem. Brit. Anim. p. 432. 



„ pliaseoUna, Lam. Anim. s. Vert. (ed. Desh.) vol. vi. p. 120 (badly). 



Thracia pliaseoUna, Kiener, Coq. Viv. Thracia, pi. 2, f. 4. — Storer, Translat. 

 Kiener, p. 7. — Desh. Elem. Conch, pi. 9, f. 4, 5. — 

 CouTHouY, Host. J. of Nat. Hist. vol. ii. p. 147. — Hanl. 

 Recent Shells, p. 22, snpp. pi. 1 0, f. 35. — Philippi, Moll. 

 Sicil. vol. ii. p. 16. — Loven, Ind. Moll. Scandin. p. 46 

 (probably). 

 Odondneta papyracea, Costa, Test. Sicil. p. 23, pi. 2, f. 1, 2, 3, 4. 

 Thracia puhescens, Macgillivray, Moll. Aberd. p. 296. — Brown, 111. Conch. 

 G. B. p. 110, pi. 44, f. 6. 

 „ declivis, Brit. Marine Conch, f. 70. 



Dr. Turton, who was the first British writer to detect 

 the specific distinctness of the present species, has curiously 

 enough figured a variety of it as the young of ]mbescens. 

 Its nearest congener is, however, the T. mliosmscula, to 

 which species we refer our readers, for the exposition of 

 their points of difference. The T. phaseolina is of an oval 

 oblong shape, very thin and fragile, snowy white under 

 its yellowish epidermis, not at all pellucid, rather glossy, 

 and very inequivalve ; the margin of the more convex valve 

 (and both are moderately so) embracing the other through- 

 out its entire circumference. The surface, which is marked 

 with obsolete concentric wrinkles, only appears shagreened 

 when viewed with a powerful lens or microscope. The 

 ventral margin, which in front varies from arcuated to 

 moderately convex, and ascends behind in a rectilinear or 



