CYPRINA. 129 



stride. Color pale ycllowisli-greeii, with fine pcncillings of dusky 

 radiations. There is a remote lateral tooth on the anterior margin. 

 Diameters, one fourth of an inch ; width, one tenth of an inch. 



This shell was described from a single valve found by Rev. James 

 H. Linsley at Stonington, Connecticut, in the stomach of a haddock. 

 New Bedford llarl)or, in four fathoms gravel (^Pririie and Stu/ip- 

 Hoti) ; on the coast of South Carolina (^Kurtz), where it also occurs 

 in post-pleiocene deposits. Its peculiar form, and the line radiating 

 striae between the ribs, are peculiar. 



Genus CYPBI]\A, Lam. 1818. 



Shell obliquely heart-shaped, beaks prominent ; hinge with three 

 unequal, diverging cardinal teeth, and a remote marginal one ; pal- 

 lial impression simple. 



Cyprina Islandica. 



Shell ponderous, ventricose, round-ovate, inequipartite, shortest and com- 

 pressed anteriorly ; lunule none ; epidermis chestnut-brown, thick, and coarsely 

 wrinkled ; edge simple. 



PectuncuJus maximus, Lister, Conch, t. 272, fig. 108. 



Pectunculus cmssus, Da Costa, Brit. Conch. 183, pi. 14, fig. 5. 



Venus IslandicM, Lix. Syst. Nat. 1 131. — Gmelin, Syst. 3271. — Montagu, Test. Brit. 

 114. — Maton and Rackett, Lin. Trans, viii. 83. — Wood, in Lin. Trans, vi. t. 17, 

 figs. 1,2; Index Test. pi. 7, fig. 41 ; Dorset Catal. 3.5, pi. 6, fig. 5. — Dillavyx, 

 Catal. i. 176. — Chemn. Conch, vi. 340, pi. 32, figs. 341, 342. — Donovan, Brit. 

 Sliells, iii. pi. 77. — Muller, Zool. Dan. i. 29, pi. 28, fig. 5. — Turton, Conch. 

 Diet. 238. — R6.mer, Krit. Untersuch. 36. 



Venus mercenaria. Pennant, Brit. Zool. iv. 94, pi. .53, fig. 47. 



Venus bucardiuin, Born, Mns. pi. 4, fig. 11. 



Ci/prina Islandica, Lam. An. sans Vert. 2d ed. vi. 290. — Deshayes, Encyc. Me'th. Vers, 

 i. 46, pi. 272, fig. 6. — Blainv. Malacol. pi. 70 his, fig. 5. — Turton, Brit. Biv. 135. 

 — Fleming, Brit. Anim. 444. — Hanley, Recent Shells, i. 65. — Soweeby, Thes. 

 Conch, i. pi. 168, figs. 1, 2, 3. — Forhes and Hanley, Br. Moll. i. 441, pi. 29, pi. M. 

 fig. 4 (animal). —Loven, Ind. INIoll. Sc. 38. — Crouch, Intr. Conch ])1. 7, fig. 2. — 

 Gray, Cat. Br. Mus. (Br. Moll.) 9. — Adams, Gen. ii. 444, pi. 110, figs. 4, 4a. — 

 CiiENU, Man. Conch, ii. 103, figs. 458-460. —Kuster, in Chemn. 2d ed. (Venus) 

 pi. 5, figs. 1, 2. — Deshayes, Cat. Br. Mus. (Biv.) 200. — Reeve, Conch. Syst. pL 

 65; Elcra. Conch, ii. 114, fig. 190. 



Cyprina vulgaris, Sowerby, Genera, pi. 38, fig. 11. — Brown, Conch. 111. 93, pi. 31, fig. 

 1 ; Conch. Man. fig. 116. —Reeve, Conch. Syst. pi. 65. 



Arctica vulgaris, Schum. Nouv. Syst. 145, pi. 13, fig. 3. 



Cypnna arctica, Bowd. El. Conch. 11, fig. 33. 



Shell large, thick, and heavy, ovate-orbicular, tumid ; beaks ele- 

 vated, pointed, turned forwards and inwards so as to come nearly 



