250 SOLENID^E. 



S. ENsis, Linnaeus. 



Resembling *S'. siliqua, but arcuated, and generally more slender. 



Plate XIV. fig. 2. 



Solen ensis, Linn. Syst. Nat. p. 1114. — Penn. Brit. Zool. ed. 4, vol. iv. p. 84, 

 pi. 45, f. 22.— Da Costa, Brit. Conch, p. 237.— Pulteney, 

 Dorset, p. 28.— Donov. Brit. Shells, vol. ii. pi. 50.— Mont. Tes- 

 tae. Brit. p. 48. — Linn. Trans, vol. viii. p 44. — Turt. Conch. Dic- 

 tion p. 1 60, f. 61 ; Dithyra Brit. p. 82.— Flem. Brit. Anim. p. 459. 

 — Macgill. Moll. Aberd. p. 282.— Brit. Marine Conch, p. 35.— 

 Brown, 111. Conch. G. B. p. 1 13, pi. 47, f. 10.— Chemn. Conch. 

 Cab. vol, vi. p. 47, pi. 4, f. 30 and C— Poli, Test. Sicil. pi. 11, 

 f. 14, —Wood, General Conch, p. 122, pi. 28, f. 1, 2.— Dillw. 

 Recent Shells, vol. i. p. 59. — Lamarck, Anim. s.Vert. (ed. Desh.) 

 vol. vi. p. 55. — Index Test. pi. 3, Solen, f. 6. — Burrows. Conch. 

 pi. 4, f. 3, 4. — Philippi, Moll. Sicil. vol. i. p. 4, and vol. ii. p. 5. 

 — Sowerbv, Conch. Manual, f. 60. — Hanl. Recent Shells, p. 

 11.— Desh. Exp. Scicn. Alger. Moll. p. 184, pi. XI. f. 1, 4. 

 (animal). 



Sole7i Sahrc, Chenu, Traite Elem. p. 41, f. 126, and pi. 1, f. 1. 

 Encycl. Method. Vers, pi. 223, f. 2. 



The description of siliqua is so nearly applicable to the 

 present species, that it is only necessary to particularize 

 those few points of difference by which they may be dis- 

 tinguished from each other. 



Of these, the most readily perceptible is the decided 

 arcuatiou of the valves in eusis, which typically, likewise, 

 is far more slender in proportion, the length of ordinary 

 individuals being eight times their breadth. The anterior 

 extremity, moreover, is not truncated but rounded, whereas 

 in characteristic examples of the preceding species, the 

 convexity of the front margin is so trifling as scarcely to be 

 noticeable. The posterior side is likewise a little tapering 

 near its termination. The colouring matter is perhaps of a 

 browner tint, and the epidermis, which, as in siliqua, is 

 transparent and colourless upon the diagonally-parted-ofF 



