252 SOLENID^.. 



inhabits the sandy coast generally of Ireland" (Thomp- 

 son) ; and is taken at Lochs Carron, Kishon, Torridon (Jef- 

 freys), and other parts of Scotland. It ranges throughout 

 the European Seas, and occurs fossil in Pleistocene beds. 



The S. ensis of transatlantic writers, judging from the 

 description of Gould (Invert. Massachus. p. 28), and the 

 figure of Conrad (Americ. Marine Conch, pi. 5, f. 1,) does 

 not exactly coincide with our shell ; it is represented by 

 the latter as of a much more abbreviated form, and as 

 obliquely truncated at the shorter end. 



S. PELLUciDus, Pennant. 



Small, subarcuated, very thin ; the hinge not terminal. 

 Plate XIII. fig. 3. and (animal) Plate I. f. 2. 



Solen peUucidus, Penn. Brit. Zool. ed. 4, vol. iv. p. 84, pi. 46, f. 23 ( not 



Spengler, 1794). — Mont. Test. Brit. pp. 49, 565.— Donov. 



Brit. Shells, vol. v. pi. 153. — Linn. Trans, vol. viii. p. 44.— 



TuRT. Conch. Diction, p. 160 ; Dithyra Brit. p. 83. — Flem. 



Brit. Anim. p. 459.— Macgill. Moll. Aberd. p. 283. — Brit. 



Marine Conch, p. 35, f. 106. — Brown, 111. Conch. G. B. p. 



113, pi. 47, f. 4.— Wood, General Conch, p. 123, pi. 28, f. 



3. — DiLLW. Recent Shells, vol. i. p. 60. 

 Solen pygmatis. Lam. Anira. s. Vert. (ed. Desh.) vol. vi. p. BQ. 

 Solcn tenuis (?) Philippi, Moll. Sic. vol. i. p. 6, pi. 1, f. 2. 



This delicate and fragile shell is of a linear and slightly- 

 arcuated form, very thin, more or less compressed, and 

 everywhere covered by a polished epidermis of a greenish 

 yellow, beneath which the surface is uniformly whitish, 

 both externally and internally. The length of the valves 

 is about four times their breadth ; they are extremely in- 

 equilateral, semi-pellucid, gaping at both extremities (par- 

 ticularly in front, where their margins are reflected), and 

 devoid of all sculpture or markings. The ventral and dor- 

 sal edges run nearly parallel, so that the latter is retuse, 



