'22 C01^CH\LIA~D£THYRA. 31. 



Turf on, Conch. Diet. p. 177. 

 Venus sinuosa. Donovan, Britisli SheJls, ii. fab. 42, fig. 2. 

 Mus. nost. From the Western coasts, and Ireland. 



Shell hardly half an inch in diameter, somewhat orbicular but 

 produced at the hinge, very convex, thin, white, transparent, 

 finely but irregularly striate transversely : from the beaks, on the 

 , anterior side, runs a longitudinal furrow which forms a flexure 



at the margin, and a prominent angle half way towards the 

 hinge : beaiis prominent, slightly curved, with a small heart- 

 shaped impression under them on the side opposite to the flex- 

 ure: teeth extremely minute, and so obscure as hardly to be 

 distinguished by a very considerable magnifying power. 



31. DOfi A^X—LIiVNE. 



Testa transversa, tsquivalvis, incequilateralis ; latere antico 

 ohluso, brevissimo. Vardo dentibiis duobits : lateralibns 

 remotiusctdis. Ligamentum externum, ad latus hrevius. 



Shell transverse, equivalve, inequilateral ; with the anterior 

 side obtuse and very short. Hinge witii two teeth in both 

 valves: lateral teeth rather remote. Ligament external, at 

 the shorter side. 



