242 CONTRIBUTIONS TO THE BRITISH FAUNA. 



Ray. The characters which distinguish the two 

 species, are sufficiently obvious, and have been 

 pointed out with great perspicuity by Mr Dono- 

 van in his History of British Fishes, Plate li. when 

 describing the WhifF of Ray. — (Communicated 

 9th I>ecember I8O9.) 



S. Lepas fascicularis. — ^Plate xvii. fig. 4. 



Colour bluish-white, somewhat glossy. The 

 first valve is narrow at the top, gradually swelling 

 downwards to about one- third of its length from 

 the base, where it forms an acute knob or apex ; 

 it then bends inwards, and increases in breadth to 

 the base, where it is shaped like a hatchet. It 

 has an elevated keel, which in some specimens ex- 

 tends from the knob to the top, and in others 

 through the whole length of the shell. It is 

 wrinkled, and the wrinkles are parallel to the mar- 

 gin, and diverge from the knob towards the edge. 

 The large valves are obtusely triangular, with fur- 

 rows parallel to the inner margin, and are diver- 

 gingly streaked from the under point. They pro- 

 ject a little at the base. The two upper valves 

 are triangular, furrowed parallel to the inner mar- 

 gin, and are divergingly streaked from the upper 

 point, which is a little produced and recurv- 

 ed. The valves are connected together by a 

 transparent colourless skin. The peduncle is from 

 half an inch to near a foot in length, thin, 

 pellucid, smooth, and of a dusky colour when the 

 animal is alive. The shell, which is thin, semi:^ 



