History of British animals - University of Guam Marine Laboratory

454 MOLLUSCA. TEREDINADiE. TeredoGen. CYRENA.— Suborbicular, with three primaryteeth ineach valve, and transverse lateral teeth ;ligament on thelongest side.1. C. pidchra Suborbicular convex, smooth, slender; posteriorly truncated;one sharp-edged and two bifid teeth in each valve ; lateral teethplain and obtuse.— Cyclas pulcher, Sower. Min. Conch, t. Dxxvii. f. 1. —Hampstead, Isle of Wight, Professor Sedgwick.TEREDINAD^.Gen. CXXXI. TEREDO. Ship Worm.—Shell orbicular,hemispherical, equivalve ; hinge with a long curved toothin each valve, inserted under the margin ; ligament imperfect,the tube open at both extremities. Burrowing inwood.* The ear-shaped process on the inside of' the valves, at theouter angle under the hinge, having the inner margin detached,and forming a straight transverse edge, and the outermargin much reflected.— 548. T. bipinnata.— Accessorial appendages long, linear, andfeathered ; an obliquerib on the margin above the teeth.Turt. Conch. Diet. 184, t. xi. £38, 39, 40.; Biv. Brit. 15—In driftedtimber, Exmouth.Diameter upwards of three quarters of an inch ; tube simple ;appendagesabout the tenth of an inch in diameter ; silvery white, with numerous pearlytubercles, the outer half with verticillate, lanceolate, fringed filaments—This is nearly allied to T. palmulatus of Lamarck.— 549- T. malleolus. — Accessorial appendagestransverse andmallet-shaped, with a slender point risinglike a handle fromthe middle.Turt. Biv. Brit. 255. t. 2. f. 19.—Drifted timber, Torbay.Diameter about a quarter of an inch ; striae on the triangular processes remote;the tube consists of a slight testaceous deposit on the surface of thechamber, the termination of which is slightly semiconcamerated.** The ear-shaped process with the inner margin on the insidefurnished with a rib only, and not a detached margin,and the outer edgeis not reflected.550. T. navalis. — Accessorial appendages elongated andspoon-shaped.Linn. Syst.i. 1267 Penn. Brit. Zool. iv. 147- Mont. Test. Brit. 527.Home, Phil. Trans. 1820, 278. t. xii. f. 3. Turt. Biv. Brit. 14. t. ii.f. 1, 2, 3 In timber exposed to the sea ; the scourge of shipping.