120 ' CONCHYLI A— DITHYI?^. 29. 



Shell orbicular and nearly equilateral, with arched striae which form 



right angles at both the sides. 

 Tellina divaricata. Linn. Syst. Nat. p. 1 120. 



Gmelin, Syst. p. 3241. 



Turton, Linn. Syst. iv. p. 196. 



Chemnitz, vi. p. 134, tab. 13, fig. 129. 



Wood, Conch, p. 195, tab. 46, fig. 6. 



Dillwyn, Descript. Catal. p. 102. 



Turton, Conch. Diet. p. 178. 

 Cardium arcuatum. Montagu, p. 85. tab. 3, fig. 2. 



Pennant, Brit. Zool. iv. p. 190. 



Linn. Trans, viii. p. 67. 



Turton, British Fauna, p. 153. 

 Pectunculus parvus. Lister, Conch, tab. 301, fig. 142. 

 Mus. nost. South of Devon, Teignmouth beach. 



Shell half an inch in diameter, white, thin, brittle, orbicular with 

 a slight flexuosity on the hinder side, rather convex, with regular 

 but not very close striae which form rather oblique curved lines and 

 turn ofi" at both the sides nearly in right angles : beaks central, very 

 prominent : hinge with a single cloven tooth in one valve, closing 

 between two plain ones in the other ; the lateral teeth remote and 

 small. 



The few specimens which we collected on the shores at Teign- 

 mouth, answer exactly to the above character and description, and 

 diflfer materially from the Tellina digitaria of Linne. 



This latter shell has very fine and uniform obliquely arched striae, 

 like the lines at the ends of the fingers, with a slight angular cur- 

 vature on one side only ; the lateral teeth are obscure, consisting of 



