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Show 702 DR. GWYN JEFFREYS ON THE MOLLUSCA OF THE [June 7, riety), 16 (var. rotunda), 17 (same variety), 17a (same variety), 22 (var. rotunda), 24 (var. polygona), off C. Sagres (same variety), 26-28a, 29 and 30 (var. polygona) ; Mediterranean, Cartagena ±5. (var. polygona), 50, off Jijeli, G. Bona, Rasel Amoush (var. polygona), G. Tunis, Adventure Bank. DistriBution. Spitzbergen, Siberian coasts, Iceland and Greenland to the Archipelago and Adriatic, Mogador, Canaries, Azores, Labrador to St. Thomas and Gulf of Mexico, Queen-Charlotte Islands, west coast of North America, and Korea; 2-1012 fms. Fossil. Miocene, Pliocene, and Post-tertiary: Smith's Sound, Norway, Great Britain and Ireland, Belgium, France, Italy, Madeira, and United States ; 0-80 ft. Extremely variable in shape, size, and consistency; one of the numerous synonyms is Cryptodon oBesus of Verrill. The variety rotunda resembles Axinopsis orBiculata of G. O. Sars, but is destitute of a cardinal tooth ; that shell appears to be restricted to the arctic zone, and I dredged it at Holsteinborg, on the coast of Greenland, in 10 fathoms. Lucina sinuosa of Donovan, as described and figured by Homes, who referred it to the Tellina flexuosa of Montagu, is not the present species. Donovan's shell is Thracia distort a. 2. AXINUS ORBICULATUS, Seguenza. (Plate LXL fig. 5.) Verticordia orBiculata, Seg. Sulle Verticordie fossili del plioceno Italiano (R. Accad. d. Sc. fis. e matem., 1876), p. 9. ' Porcupine' Exp. 1869 : St. 23. 1870 : Atlantic, 3, 6, 25-30. DistriBution. Bay of Biscay (' Travailleur' Exp.), Naples and Sicily, Canaries ; 49-645 fms. Fossil. Pliocene : Calabria and Sicily. A. granulosus, Jeffr. (MS.). Not A. {Kellia) orBicularis of Searles Wood, nor Axinopsis orBiculata of G. O. Sars. This species is smaller than A. flexuosus, and is more triangular, with prominent beaks ; and it has two ridges in the middle, and a remarkable granular epidermis. 3. AXINUS TORTUOSUS1, Jeffreys. (Plate LXL fig. 6.) S H E L L oval, obliquely twisted to one side, convex, thin, glossy, and semitransparent; sculpture, irregular concentric lines of growth : colour pale yellowish-white : epidermis filmy : margins rounded in front and at the sides ; below the beak, on the posterior side, that part of the margin is excavated ; there is no fold or furrow on the anterior side : Beaks prominent, pointed, and incurved : lunule narrow, with a thickened edge: ligament elongated, enclosed in a narrow groove: hinge-line obtusely angular, occupying about one third of the circumference : hinge-plate thick, containing the ligament : teeth none : inside glossy, exhibiting faint but numerous longitudinal strise : pallial scar narrow and distinct: muscular scars inconspicuous. L. 0*175, B. 0*2. ' Porcupine ' Exp. 1870 : St. off C. Espichel; a single valve. DistriBution. Bay of Biscay (' Travailleur' Exp.); 645-1012 fms, ' Twisted, |