362 Dr. Turton on some new British Shells, 



Shell bivalve, equivalve, equilateral, transverse ; with a large 

 oval gape at the front margin. Hinge without teeth. Ligament 

 internal. 



Length two lines and a half; breadth not quite half an inch. 



This new and very singular bivalve, we dredged up in the Eng- 

 lish Channel, alive, during a gale of wind. The shell is very tumid 

 in the middle, and gradually sloping to the sides, which are 

 rounded and closed. The colour is of a dull milky white ; and 

 the surface covered with short, close-set, transverse, interrupted, 

 opake lines, very irregularly disposed, and which give the margin 

 a serrated appearance. The beaks are rather prominent and cen- 

 tral ; the cardinal margin running nearly straight ; but the front 

 margin a little rounded, with a large oval eye-like transverse gape, 

 extending the whole breadth. 



In the Linnean arrangement it would rank with the Mi/ce. 

 Dr. Goodall, who carefully examined our specimen, thinks he has 

 somewhere seen a single valve, which from the peculiar markings 

 of the surface, cannot be mistaken for any other known shell. 



Icon. tab. xiii. fig. 1. 



Mus. nost. 



2. Lima tenera. 



Testa compressa^ incequilaterali^ utrinque hiante ; latet^e antico 

 subtrigono^ peritremate intus marginato : costis 25 ; subun- 

 datisy leeviusculis; margine serrato; car dine obliquo. 



Shell compressed, inequilateral, open on both sides; the an- 

 terior side somewhat triangular, with the aperture margined in- 

 ternally : ribs 25, somewhat undulated, and nearly smooth : the 

 margin serrated ; and the hinge oblique. 



Length an inch ; breadth five eighths of an inch. 



This shell does not seem to agree exactly with any of the 

 species described by authors. It differs from the Lima Loscombi^ 

 our L, bullata, in being much more depressed ; in having fcAver 



forms us that he has two other species, one from the Mauritius and the other 

 from Van Diemen's Land; it is therefore necessary that a specific name should 

 be given to this species, and we have chosen Turtoni, in honour of the first 

 describer of the genus. — Editors. 



