312 



T. testa ovata aut obovataj magis minusve ventricosa, solidius- 

 cula, siibnitida, sublsevigata, subsequilaterali, extus intusque albida, 

 lineis obsoletis pallidioribus subradiata, epidermide pertenui lutes- 

 ceute iiiduta; margine ventrali antice arcuato, postice sursiun 

 acclinato; dorsali autice prope nates acutas subrecto deindeque 

 arcuato et subdeclivi, postice subretuso et valde decli^^; latere 

 aiitico longiore, rotmidato ; postico attenuato^ angulato, et paululum 

 subrostrato ; flexura costaque umbonali satis conspicuis ; Hgamento 

 prominulo ; dentibus minimis. 



Ovate or obovate, more or less ventricose^ not very strong, 

 ratlier glossy, nearly equilateral, wliitisli both within and without, 

 covered by a very tliin yellowish ash-coloured epidermis, nearly 

 smooth being merely wrinkled by the lines of growth, peculiarly 

 marked with obsolete radiating lines; ventral edge arcuated in 

 front and rising beliind ; anterior side rather the longer, its extre- 

 mity rounded, its dorsal edge at first nearly straight and then 

 arched and moderately sloping; posterior side attenuated, angu- 

 lated, and very slightly beaked ; fold and flexure tolerably clistinct ; 

 ligament short and shghtly prominent ; teeth very small. 



Gambia. 



In typical examples there is a slight groove-like depression 

 beliind the fold, which does not exist in the next species. 



178 Tellina Cayennensis (pi. Ixii. f. 190.) Psammobia C. 

 Lam. no. 11 ; Hani. Des. Cat. p. 58. sup. 1. 11. f. 48 ; Deles. Rec. 

 t. 5. f. 7 ; T. constricta, Phil., Ab. und Bes. Conch, part 3. t. 5. 

 f. 5 ; T. intastriata. Say, Jour. Ac. Nat. Sc. Philad. 



T. testa ovali-trigona, sohda aut solidiuscula, magis minusve 

 ventricosa, subinaequivalvi, subinsequilateraU, nitidiuscula, extus 

 intusque albida, epidermide cinerascentc induta, sublajvigata ; mar- 

 gine ventrali convexiusculo ; dorsali antice convexo et subdeclivi, 

 postice subrecto et declivi ; latere antico paulo longiore, rotundato ; 

 postico cuneiformi; natibus rccte incurvatis; hgamento promi- 

 nido, satis magno; flexura costaque umbonali satis conspicuis; 

 dentibus baud parvis. 



Triangularly-oval, more or less sohd and ventricose, slightly 

 inequivalve and inequilateral, scarcely glossy, nearly smooth, wliitish 

 witliin and without, covered by a very tliiu ashy epidermis ; ven- 

 tral edge slightly convex ; dorsal convex and moderately sloping 

 in front, straightish (never incurved) and strongly sloping behind ; 

 front side roimded, rather the longer ; hinder side wedge-shaped ; 

 beaks incurved ; hgament Httle prominent, and as well as the teeth, 

 of a moderate size ; fold and flexure tolerably distinct. 



