CONCHYLIA— D/T/fyj?^. 10. 87 



Mus. nost. Rocks in Torbay. 



Shell a quarter of an inch long, and half an inch broad, covered 

 with a brown wrinkled skin which extends beyond the anterior end, 

 wedge-form, truncate at the hinge, with the upper margin often a 

 little contracted about the middle, gradually tapering to the ante- 

 rior end which is slightly open ; beaks rather prominent, with the 

 points not quite opposite but divaricating from each other : inside 

 glossy white with a purplish tint, the margin sharp and plain ; the 

 elevated tooth running in a gradually narrower and wedge-shaped 

 manner nearly half way along the back margin. 



Except for the very distinct and visible teeth, we should be much 

 iflolined to think that this is the Mytilus praecisus of Montagu, p. 

 165, tab 4, fig. 2. He speaks of his shell as not being uncommon 

 among rocks, subject to much variety of shape ; and some of our 

 specimens much resemble his figure. 



Named from General Bingham, our diligent fellow-labourer among 

 the rocks in Torbay. 



Sphenia testa ovato-cuneatd, dente concavo horizontali-protenso. Swainsoni. 



Shell oval-wedge-form, with the concave tooth projecting hori- " 

 zontally inwards. 



Tab. nost. 2, fig. 3, and tab. 19, fig. 2. 



Mus. nost. From rocks in Torbay. 



Shell about the size of the last : but is of a more oval form, with 

 the anterior end rounded, the beaks not so near the end, and the 

 concave tooth projects inwards like those of Anatina prcetenuis. 



