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Show 52 DR. GWYN JEFFREYS ON THE MOLLUSCA OF THE [J genera and species on a very extensive scale, he is of course at perfect liberty to please himself; time, however, will show whether other concho'logists will adopt them.' And I would also observe that it is unusual, if not discourteous, to so positively and ex cathedra contradict other writers-who have the same means and ability as himself for judging as to the authority of species previously published -without offering some reason for his dissent from their opinion. Genus STILUS \ Jeffreys. S H E L L spit-shaped, reticulated; apex forming a twisted and abruptly semidetached peak; basal groove short and recurved. The peculiarity of this genus consists in the apex, which is different from that of any other genus which I know. I consider this character important. STILUS INSIGNIS2, Jeffreys. (Plate VI. figs. 1-1 ft.) S H E L L obeliscoid, rather thick, opaque, but glossy: sculpture, numerous and somewhat curved longitudinal ribs, of which there are from 30 to 40 on the last whorl; these are crossed by 3 spiral striae on each whorl, so as to cause by their intersection minute tubercles on the striae ; the periphery is encircled by a slight ridge ; the base is quite smooth and somewhat concave ; the ribs on the apical or top whorls are very few and flexuous : colour white: spire tapering, and abruptly terminating in a short, twisted, and upturned point : whorls 10-12, flattened, and gradually enlarging; the last equals about one third of the shell: suture narrow, but well defined : mouth small, squarish, with a short recurved groove turning to the left, as in typical species of this family : outer lip thin, scalloped or indented bv the spiral striae : inner lip inconspicuous: pillar flexuous. L. 0r25, B. 0-075. ' Porcupine ' Exp. 1870: Atl. St. 29, 31-34. Several specimens. L,EOCOCHLIS GRANOSA, Searles Wood. C. granosum, S. Wood, Crag Moll. 1848, p. 73, pi. viii. f. 9. L. granosa, G. O. Sars, Moll. reg. arct. Xorv. p. 190, t. 13. f. 6. ' Lightning ' Exp. St. 2. 'Porcupine' Exp. 1869: 23a, 65, 89, 90. Distribution. Norway from Finmark to Bergen, North Sea Exp. (Metzger) ; 30-300 fms. Fossil. Pliocene : Red and Coralline Crags, Antwerp Crag (Brussels Museum, as C. sinistrutum of Nyst, although the species described and figured by him is apparently different) ! Triforis macandraa of H. Adams, Triforis nivea of M . Sars's MS., and Lceocochlis pomeranice of Dunker and Metzger. The spire in I his singular genus, which was established by Dunker and Metzger, is reversed or sinistrorsal; the basal groove is recurved and twisted ; and the apex is sculptured, as in typical species of 1 Having the shape of a Eoman style or instrument for writing on waxen tablets. 6 2 Remarkable. |