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Show 942 DR. G W Y N JEFFREYS O N THE MOLLUSCA OF THE [Nov. 29, 14. NE.ERA CIRCINATA, Jeffreys. (Plate LXXI. fig. 6.) N. circinata, Jeffr. in Ann. & Mag. N. H. Dec. 1876, p. 497. 'Porcupine' Exp. 1869: St. 23 (a fragment). 1870: Atl. 16 (a small valve). Distribution. Bay of Biscay ('Travailleur' Exp.), N. Atlantic ('Valorous ' Exp.), W . of Azores ('Challenger' Exp.); 600-1450 fms. N. imBricata, Jeffr. MS., is a synonym. 15. NEJERA RUGINOSA1, Jeffreys. (Plate LXXI. fig. 7.) S H E L L roundish-oval, somewhat depressed, thin, semitransparent, and rather glossy: sculpture, numerous fine and concentric minute strise, which become wrinkly towards and on the posterior side : colour white: margins rounded equally on the anterior side and in front; rostrum very short and obliquely truncated; dorsal margin lying beneath the umbo, short and scarcely curved on the anterior side, half as long again and straight on the other side : Beaks minute, circular, and sunken ; umbo small and prominent: cartilage-pit minute, narrow, and placed obliquely: hinge-line nearly straight: hinge-plate thin, slightly reflected on the anterior side : teeth, none in the left valve, the right valve not having been found: inside polished : scars inconspicuous. L. 01, B. 0*15. 'Porcupine' Exp. 1870: Atl. St. 17, 17a. Three left valves only. This small species might be mistaken for the young of N. circinata ; but the sculpture is very different, and the rostrum is much shorter. 16. NE^RA INFLATA2, Jeffreys. (Plate LXXI. fig. 8.) S H E L L equivalve, roundish-oval, with an oblique outline, gaping posteriorly, globose, rather solid, semitransparent, and glossy : sculpture, very numerous, fine, and close-set concentric strise, which are observable with the naked eye ; they are more irregular and sometimes wanting, or become wrinkly, on the rostrum : colour pale yellowish-white : epidermis filmy : margins rounded on the anterior side and in front; rostrum short and bluntly pointed, appearing as if pinched up, and separated or defined by a shallow indentation ; it is occasionally somewhat angulated and marked by a slight keel or ridge, which is more distinct in the young; dorsal margin upraised on the anterior and down-sloping on the posterior side : beahs triangular, incurved towards the anterior side; umbones very prominent: cartilage-pit oblong, narrow, and obliquely projecting inwards: hinge-line obtuse-angled : hinge-plate thin, a little reflected anteriorly : teeth, a small upright triangular cardinal and a long laminar lateral on each side in the right valve, besides a long laminar lateral on the posterior side, and parallel with the hinge-plate in the left valve: inside polished, furnished on the posterior side in each valve with a strong and curved laminar process or ridge, which apparently 1 Wrinkled. 2 Swollen. |