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Show 676 DR. G W Y N JEFFREYS ON THE MOLLUSCA OF THE [Nov. 14, 'Porcupine'Exp. 1870: Atl. St. 16, 17, 17a. Several specimens. Distribution. 'Valorous' Exp., Bay of Biscay ('Travailleur' Exp. 1881); 1003-1450 fms. Off Culebra I., Danish W . Indies (' Challenger' Exp.) ; 390 fms. This is easily distinguishable from any species of Fissurisepta in having a conspicuous and persistent spire, as well as in the shape of the septum. The only difference between Puncturella and Rimula seems to consist in the comparative length of the slit. This is proportionally much longer in the young than in the adult of the typical species, P. noachina. 2. PUNCTURELLA NOACHINA, Linne. Patella noachina, L. Mant. Plant, p. 551. Puncturella noachina, B. C. iii. p. 257, pl. vi. f. 3; v. p. 200, pl. lix. f. 1. 'Lightning' Exp.: St. 2, 4, 5, off the Faroe I. 'Porcupine' Exp. 1869: St. 6, 9, 13, 14 (and var. princeps; and var. levior, laterally compressed, keeled in the line of the slit or fissure, and nearly smooth), North Channel, 70, off Lerwick. 1870 : Atl. 2, 3a, 17, 17a, 24, 27, 28. Distribution. From Wellington Channel and Greenland to the southern coast of New England, Iceland, Spitzbergen, and Jan Mayen I. to Scarborough, Novaia Zemblia, Okhotsk Sea, N . Japan, and Corea, Strait of Magellan (Acton and ' Challenger' Exp.), between C. of Good Hope and Kerguelen I. ('Challenger' Exp.); 4-430 fms. Fossil. Miocene? : Sicily. Pliocene: Coralline Crag and S. Italy. Post-tertiary : Scandinavia, Scotland, and Yorkshire, Sicily, and Labrador, mostly in " glacial" deposits ; 0-470 ft. The odontophore has been well figured by Friele, and shows that it is of a Rhipidoglossan type. The genus Cemoria of Leach MS., as defined by Risso, is certainly not the genus Puncturella ; his type is doubtfully referred to the Patella equestris of Linne. 3. PUNCTURELLA CLATHRATA1, Jeffreys. (Plate L. fig. 11.) S H E L L forming an oblong cone, rather solid for its size, opaque and lustreless: sculpture, numerous fine longitudinal striae and stronger concentric ridges, the intercrossing of which produces a cancellated appearance ; the striae do not reach much beyond halfway from the margin, where the ridges become slighter and crowded up to the apex : colour pale brownish white : beak smooth, incurved, twisted a little to the left, and ending in a spire of a single whorl: foramen forming a long triangular slit: mouth oblong : margin finely scalloped: inside smooth and glossy : septum large, triangular as in P. profundi. L. 0*15, B. 0*1. 'Porcupine' Exp. 1870: Atl. St. 17a. A single and somewhat imperfect specimen, but peculiar and characteristic. 1 Latticed. |