368 TELLINIDiE. 



pale yellowish -white : epidermis fibrous, usually worn off and 

 only visible near the beaks and at the edges of newly-formed 

 layers : margins curved, but not deeply, in front, nearly semi- 

 circular on the anterior side, acutely angular but bluntly 

 pointed at the posterior end, whence there is a long and nearly 

 straight slope backwards : beaks small, incurved, and con- 

 tiguous (frequently becoming worn by attrition) : ligament 

 strong and prominent, horncolour, annulated at irregular in- 

 tervals : hinge-line obtusely angular : hinge-plate thick, re- 

 flected outwards on the dorsal side, where it terminates ab- 

 ruptly near the extremity of the ligament : teeth, in the right 

 valve two cardinals of unequal size representing the letter V 

 reversed, and receiving between them the larger tooth of the 

 opposite valve ; in the left valve two cardinals, that on the 

 posterior side being very large, recurved, irregularly divided by 

 a groove, or double, and the other on the anterior side very 

 much smaller, triangular, and parallel with the hinge-plate : 

 inside partially nacreous, stained with yellow near the beaks 

 and on the posterior side : pallial scar exhibiting a wide but 

 not deep sinus : muscular scars of irregular shape, equal-sized. 

 L. 1-05. B. 1-5. 



Habitat: Not uncommon, although very local, in sand, 

 from low-water mark to 12 fathoms. Weymouth (Thomp- 

 son) ; Guernsey (J. G. J.) ; near Tenby (Lyons) ; coast 

 of Pembrokeshire (M 'Andrew) ; south and west of Ire- 

 land (Turton, Humphreys, Battersby, King, and others) ; 

 Shetland Isles (Forbes, in Brit. Assoc. Bep. 1850). Dr. 

 Turton found it in a semifossil state at Clontarf in 

 Dublin Bay, imbedded in blue clay with Tapes aureus. 

 The only northern locality that has been noticed for 

 G. fragilis is Drontheim, where Mr. M' Andrew dredged 

 a single valve. The southern localities are very nume- 

 rous, and comprise all the coasts of the Atlantic from 

 Brittany to Gibraltar, the Mediterranean on both sides, 

 x\driatic, and iEgean. The greatest depth that I can 

 find recorded is 30 fathoms ; and it is littoral at Vigo 

 and in the iEgean. Searles Wood has noticed its 

 occurrence in the " faluns " of Touraine, and Philippi 



