70 INVERTEBRATA OF MASSACHUSETTS. 



t. 33, f. 399. Deshayes; Encyc. Mdth., Vers., ii. 379. Lam.; An. sans Vert., 



vi. 225. 

 Venus borealis, Donovan ; Brit. Shells, iv. pi. 130. 

 Venus spuria, DiLi.wyN ; CrtZaZ., 194. Gmelin ; S?/5f., 3284. 

 Pectunculus subfuscus, Lister : Conch., I. 293, f. 129. 



Shell white, thick, orbicular, regularly but moderately convex ; 

 hinge margin straight ; beaks small, pointed, slightly prominent, 

 inclining forwards over a small, indented, smooth, lanceolate 

 lunule ; on each side of the hinge runs a shallow furrow, which, 

 terminating in the margin, causes a slight undulation. Surface 

 covered with fine concentric, lamellar ridges, in the intervals of 

 which are often seen minute, radiating lines ; interior chalky- 

 white, except around the margin, where it is polished ; with 

 radiating lines, most apparent near the margin. Hinge straight, 

 without lateral teeth, and with a single cardinal tooth in the left 

 valve, and two small, diverging ones in the right. Anterior mus- 

 cular impression very narrow, and directed obliquely to the 

 centre of the valves. Length 1^ inch, height the same, breadth 

 yV inch. 



This must be considered a rare shell, and an inhabitant of deep 

 water. A few valves have been picked up on our beaches after 

 severe storms. It is a common shell on the other side of the 

 Atlantic. 



Luci'na divarica'ta. 



8hell while., orbicular, lenticular, sculptured icilh grooves bent 

 obliquely doiomoanls at both sides ; lateral teeth obsolete ; margin 

 dentated. 



State Coll., No. 214. Soc. Cab., No. 1792. 



Tellina divaricata, Lin.; Sijst. JVat., 1120, Gmelin ; Syst., \v. 3241. No. 74. 



BoNANNi ; Rear., iii. f. 349. Schroet.; EM. in Conch., ii. GG3. Petiv. ; 



Gaz., t. 156, f. 2G. Klein ; Ostracol., t. 9, f. 28. Favanne ; Conch., pi. 48, f. 



E. Chemn.; Conch., vi. 134, t. 13, f. 129. Brug. ; Encyc. M6th., pi. 285, f. 



4, a, b. Fqli ; rfi5<., 1. pi. 15, f. 25. Dillwvn : Ca/aZ., i. 102. No. 7. Tur- 



TON ; Conch, Diet., 178. 

 Cardium arcuitum, Montagu ; Test. Brit., 85, pi. 3, f. 2. 

 Pectunculus parvus, Lister ; Conch., t. 301, f. 142. 

 Lucina divaricata. Lam. ; An. sans Vert., vi. 226. Ann. du J\Ius., vii. 239. 



Deshayes ; Encyc. M6th., Vers, ii. 376, pi. 285, f. 4. Blainv.; Malacol. pi. 



72, f. 3, 3 a. Payraudeau; CataL, 42, No. 69. 

 Strigilla divaricata, Turton ; Brit. Biv., 119. 



