442 MOLLUSC A. LUCINADiE. Lucina 



Pectunculus subfuscus, List. Conch, t. ccxciii — Tellina radula, Mont. 

 Test. Brit. 68. t.ii. f. 1, 2 — Venus borealis, Don. Brit. Shells, t.cxxx. 

 — L. radula, Turt. Biv. Brit. 116 — Deep water on various parts of the 

 coast. 



Diameter about an inch and a half; white; lenticular, the margin slightly 

 irregular retrally ; beak prominent, slightly inclining ; the concentric striae 

 in the young shell are very regular (in which slate it appears to be the L. alba 

 of Dr Turton, Biv. Brit. 114. t. vii. f. 6, 7.), but with age they become irre- 

 gular, and less distinct towards the margin ; one of the hinge teeth cloven ; 

 right valve with an anterior lateral tooth. 



505. L. Jlexuosa. — Obsoletely striated transversely; the beaks 



prominent, and the retral margin much waved. 



Tellina flexuosa, Mont. Test. Brit. 72 — Cryptodon flexuosus, Turt. Biv. 

 Brit. 121. t. vii. f. 9, 10 — Not uncommon from Devon to Zetland. 



Diameter scarcely half an inch ; white, thin and translucent ; two grooves 

 on the retral extremity, extending from the beaks to the margin, and a 

 rounded depression before the beaks ; the teeth are indistinct, seldom more 

 than one tooth developed in each valve. It bears a very close resemblance 

 to L. pennsylvanica, List. Conch, t. cccv. 



** Strice oblique and arched (Strigella of Turton). 



506. L. carnaria. — Oval, inequilateral, with oblique stria? in 



three directions, forming acute angles retrally, and waved arches 



anteally. 



Pectunculus tenuis, List. Conch, t. cccxxxix. — Tellina carnaria, Linn. 



Syst. i. 1119 Pult. Dorset, xxx — Don. Brit. Shells, t. xlvii Mont. 



Test. Brit. 73 — Strigilla carnaria, Tuft. Biv. Brit. 117 — Weymouth 

 and Poole, Dr Pulteney. 



Diameter about |ths of an inch ; white, more or less tinged with rose-co- 

 lour, back a little inclining, under which is an oval impression. 



507. L. pisiformis. — Shell somewhat globular, and nearly 



equilateral, with oblique longitudinal striae on one side, forming 



acute angles, on the other waved. 



Tellina pisiformis, Linn. Syst. i.11120. — Cardium discors, Mont. Test. 

 Brit. 84 — Strigilla pisiformis, Turt. Biv. Brit. 119 — One dead speci- 

 men found at Falmouth by Mr Montagu. 



Diameter about a quarter of an inch ; convex, glossy white ; beaks small, 

 inclining ; two teeth in one valve, one of which is very small, one in the 

 other, with remote lateral teeth like laminae. The Strigilla divaricata of 

 " Bivalvia Britannica," appears to belong to this species. " 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 off" 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." Shores of Teignmouth. 



508. L. arcuata. — Orbicular, with oblique doubly waved stria?. 



Cardium ar. Mont. Test. Brit. 85. t, 3. f. 2 — Falmouth harbour. 



Diameter about half an inch ; white, thin, fragile, finely and regularly 

 striated obliquely, with a few irregular concentric furrows ; beak central, 

 pointed and arching; hinge with one primary tooth in each valve, lateral 

 teeth remote. 



