18 SOLENID^. 



The locomotion of this species is the same as that of 

 S. pellucidus. Its foot is permeated by a series of aqui- 

 ferous ducts or canals, causing a great expansibility of 

 that organ. Gould says that the animal is " too long 

 for the shell ; " but its power of contraction equals that 

 of its extension. A distorted specimen, found by Mr. 

 Barlee, and now in the University Museum at Oxford, 

 is bent in an extraordinary degree. Whether the curve 

 of such a crooked generation might in course of ages be 

 increased, so as to form a nearly complete circle, would 

 be a curious speculation. 



In the time of Aldrovandus it was called by the 

 Venetians "cappa longa." Linne doubted whether it 

 were not a variety of S. siliqua. The one certainly in- 

 habits deeper water than the other, and they are closely 

 related in form. The present species is Lister's S. curvus 

 (accidentally binominal), the Hypog&a falcata of Poli, 

 Ensis magnus of Schumacher, S. ensiformis of S. Wood, 

 and Ensatella Europtea of Swainson. 



y^Vj- 3. S. si'LiQTJA*ijinne.) M 



S. siliqua, Linn. S. N. p. 1113 ; F. & H. i. p. 246, pi. xir. f. 3, and (animal) 

 pi. I. f. 1. 



BODT similar to that of S. ensis, except in being rather less 

 compressed, and in the foot being yellowish -white, with its 

 extremity abruptly truncated, and marked with extremely fine 

 close-set and very pale lead-coloured lines. 



SHELL so closely resembling that of S. ensis, except in being 

 of a much larger size, that it is sufficient to mention the few 

 particulars in which they differ. This is almost straight in- 

 stead of curved, much deeper in proportion to its breadth, and 

 more solid ; the margins at both ends are abruptly truncated ; 

 the cardinal teeth in the left valve are blunter, and sometimes 

 cloven; and the lateral tooth in this valve is often double. 

 L. 1. B. 8. 



* A pod. 



