History of British animals - University of Guam Marine Laboratory

418 MOLLUSCA. CARDITADiE. Carhtta.5. C. similis.— Ithomboidal, gibbose, transversely costated ; anterior partseparated by a projecting serrated keel, lunette heart-shaped, nearly Hat ;beaks involute—Sower. Min. Conch, t. ccxxxii. £ 3.— Inferior Oolite.Gen. VENERICARDIA.—Shell inequilateral, longitudinallyribbed ; hinge-teeth two, oblique.1. V. planicosta— Subcordate, very thick, smooth, ribs broad and flat, about20, expanding into each other towards the margin ; a few longitudinal teethwithin the posterior edge.— Sower. Min. Conch, t. 1. — London Clay.2. V. senilis Obliquely cordate, thick, with large, convex, subimbricated,naked ribs; lunette obsolete—Park. Org. Item. iii. 191. t. xiii. 1*.15, 17.Sower. Min. Conch, t. cclviii—In Crag.3. V. carinala Transversely oblong, with 20, nearly smooth, carinatedribs ;lunette obsolete.— Sower. Min. Conch, t. cclix.—In London Clay.4. V. deltoidea.— Deltoid, with rounded angles; ribs 15, keel-formed ;hingecallous, beaks prominent ; lunette small—Sower. Min. Conch, t. cclix. f. 1.—In London Clay.5. V. globosa — Globose; costae 1G to 20, carinated carinte ; tuberculated,compressed— tubercles (Chama sulcata, Brander, f. 100.) Sower. Min. Conch.l. cclxxxix. upper and middle figures—London Clay.C. V. ohlonga.— Transversely oblong, unequal sided, subquadrangular, gibbose,with 13 knotted costse; length about two-thirds the width; costae strong,obtuse, irregularly knotted, margin strongly toothed—Sower. Min. Conch,t. cclix. three lower figures —London Clay.7. V. chammformis Convex, orbicular, with rather produced beaks ; ribsrugged, distant, about 14 ; hinge large— Sower. Min. —Conch, t. ccccxc. f. 1.In Crag:8. V. orbicularis— Orbicular, rather convex, concentrically striated ; ribsabout 16, not close, crenated ; hinge small—Sozver. Min. Conch, t. ccccxc.f. 2—In Crag.9. V. scaluris—Orbicular subtriangular, depressed;longitudinal sulci about20, linear, concentrically striated ; hinge-teeth long and thin—Sower. Min.Conch, t. ccccxc. f. 3—In Crag.Gen. CRASSATELLA. — Shell inequilateral; hinge withtwo strong teeth in one valve, receiving one tooth from theother ; ligament inserted in a pitat the side of the teeth.1. C. sulcata— Ovato-elongated, transversely sulcated ; anterior side produced,obliquely truncated, defined by a ridge; edge-toothed within.— (Tellinasulcata, Brander, f. 80.)— Sower. Min. Conch, t. cccxlv. f. 1.— In LondonClay.2. C. plicata.— Oblong, ovate, concentrically and minutely plicated ; plica?reflected ; anterior side defined by an obtuse ridge, obscurely truncated ;margin toothed within.—Sower. Min. Conch, t. cccxlv. f. 2.—In LondonClay.