260 MOLLUSCA FROM THE CRAG. 



Spec. Char. Testa ovato-oblongd, transversa, convexiusculd, tenui, subaquilaterali, 

 antice rotundatd, postice truncatd, et angulatd ; punctis minutissimis asperatd ; callo 

 ligamentifero magno. 



Shell ovately oblong, transverse, slightly convex, thin, subequilateral, anterior side 

 rounded, posterior truncated and angulated, exterior minutely granulated ; hinge with 

 large projecting callus, divided by a ridge. 



Length, 2\ inches. Height, 2^ inches. 



Locality. Cor. Crag, Sutton and Gedgrave. 



Clyde Beds. Smith. Recent, Britain and iEgean. 



A thin and fragile shell, not very rare, but difficult to obtain. Like most of the 

 specimens of this genus found in the Crag, they are somewhat distorted from com- 

 pression, and one or other of the valves in consequence cracked, thereby altering a 

 little the natural appearance of the shell. On closely comparing it with the existing 

 species, it may be remarked that the left valve is rather less contracted, — that is, the 

 ventral margin is more convex, or not so straight, as in the living shell, and the umbo 

 apparently less prominent ; but the few specimens that I have seen are all pushed a 

 little out of their natural position, and these trifling differences would probably 

 disappear in a larger and better series. 



2. Thracia phaseolina, Lamarck. Tab. XXVI, fig. 2, a — c. 



Myadeclivis. Turt. Conch. Diet., p. 98, 1816. 

 Anatina declivis. Id. Brit. Biv., p. 47, 1822. 



— PUBESCEN8. Id. Brit. Biv., p. 45, t. 4, fig. 3 (young). 

 Amphidesma phaseolina. Lamk. Hist. Nat., torn, v, p. 492, No. 11, 1818. 

 Thracia phaseolina. Keiner. Coq. viv. Thracia, pi. 2, fig. 4. 



— — Phil. En. Moll. Sic, vol. i, p. 19, t. 1, fig. 7, 1837. 

 Odoncineta papyracea. Da Costa. Test. Sicil., p. 23, pi. 2, figs. 1 — 4, 1829. 

 Thracia phaseolina. Forb. and Hani. Hist, of Brit. Moll., p. 221, pi. 17, figs. 5, 6 ; 



and pi. h (animal), fig. 4, 1848. 



— — Couth. Bost. Journ. Nat. Hist., p. 147, 1839. 



— — Lov6n. Ind. Moll. Scand., p. 46, No. 321, 1846. 

 Tellina papyracea. Poli. Test. Sicil., t. 15, fig. 18. 



Spec. Char. Testa elongato-ovatd, transversa, subaquilaterali, tumidiusculd, tenui; 

 antice rotundatd, postice truncatd; margine ventrali convexiusculo. 



Shell elongato-ovate, transverse, nearly equilateral, thin, and fragile ; anterior side 

 rounded, posterior truncated ; ventral margin slightly rounded. 



Length, 1 inch. Height, f- inch. 



Locality. Cor. Crag, Sutton. 



Recent, Britain, Mediterranean, Scandinavia. 



Small specimens are by no means rare at Sutton ; and as the recent conchologists 



profess to have sufficient evidence for the separation of this from the young of T. 



