34 



interrupted opaque lines very irregularly disposed 

 which gives the margin a serrated appearance ; beafrs 

 rather prominent, hinge margin nearly straight, ventral 

 edu'e rather rounded ; gape extending the whole breadth, 

 i . . . i . Guernsey, English channel. 



TRIBE. SOLENIDES. 



Transversely elongated, destitute of accessory pieces 

 and gaping only at the sides ; ligament external. 



GENUS. SOLEN. LIN. 



Equivalve, transversely elongated, gaping at both ex- 

 tremities ; beaks very small, always short : cardinal 

 teeth small, varying in number, sometimes none and 

 rarely a pit between them. 



* Hinge terminal, shell posteriorly truncated. 



S. VAGINA. Lin. 1113. D. p. 67 Lam. I. Don. 

 4. t. 110. Pen. 4. p. 83. Mont. p. 48.Turt. B. 

 p. 79- Subcylindrical, more compressed towards the 

 truncated anterior end ; posterior end slightly oblique, 

 shortest, strictured at the margin ; pale yellow longitudi- 

 nally striated and ammlated with brown : a single looth 

 in each valve ; teeth flattened on the rubbing surface ; 

 the opposite sides strengthened by a rib. 1...5. Common, 



