VENUS. 421 



tremely narrow, small, and not at all projecting. The 

 lunule is rather large, very ill defined, not sunken, but, on 

 the contrary, pouting at the lips ; it is not free from the 

 ribs which traverse the rest of the exterior. The umbones 

 are moderately prominent, and incline a little forward ; the 

 beaks are not acute. The interior is whitish or flesh- 

 coloured, with the disk occasionally of a fine reddish-purple 

 or lilac hue ; the inner margin is everywhere very deli- 

 cately but quite distinctly crenated. The hinge-margin is 

 moderately broad, and is furnished in the right valve with 

 an anterior simple and almost laminar tooth, which is so 

 oblique as almost to lie adjacent to the upper margin : both 

 the other teeth are triangular, somewhat bifid, and tolera- 

 bly strong. The central of the left valve is bifid and rather 

 broad ; both the others are simple, narrow, and very 

 oblique. 



Our engraving represents the ordinary size of fine exam- 

 ples of the adult shell. 



The animal is yellowish-white, ovate, and has very short 

 tubes. The margins of the mantle are finely scalloped, 

 and fringed and marked with reddish lineations. The tubes 

 are united nearly to their orifices, where they diverge ; 

 around the openings of each are about twenty slender and 

 conspicuous cirrhi. The colour of the tubes is sulphur- 

 yellow ; between each pair of cirrhi is a red dot. The anal 

 valve is very conspicuous. The foot is compressed and 

 linguiform, geuiculated at the base. The branchiae are 

 pale-brown. 



The Venus ovaia is universally diffused throughout the 

 British seas, inhabiting all depths of water between three 

 and nearly one hundred fathoms, often excessively abun- 

 dant. It seems to have a preference for a gravelly-sand 

 bottom. Southern specimens are often more brightly- 



