OCR Text |
Show 1880.] MR. G. F. ANGAS ON NEW MARINE SHELLS. 419 of which are stained with dark brown; canal moderate, a little recurved and partly closed by the union of the two lips at their base. Alt. 3 inches, diam. 2 inches. Hab. Port Darwin, Torres Straits (TV. T. Bednall). Another very beautiful shell, belonging to the Pteronotus group of Murices (also discovered by Mr. Bednall, and provisionally named by Mr. Brazier), which I have great pleasure in figuring in the Society's ' Proceedings.' CLANCULUS BICARINATUS, n. sp. (Plate XL. fig. 4.) Shell umbilicated, turbinate, solid, very dark purplish brown ; whorls 6, prominently keeled in the centre, the last whorl with two keels, one above and one below the periphery, sculptured all over with distinct separated rows of regular close-set bead-like nodules, those on the keels being double the size of those between them, the interstices crossed with fine oblique striae ; outer lip strongly dentate within, and surrounded by a row of black spots at the margin ; columella nearly straight, with a small tooth-like projection at either end, the margin of the false umbilicus dentate, with an incurved tooth above, and crenate at the base, around the umbilical margin white ; interior pearly white. Alt. 6, diam. 8 lines. Hab. Port Darwin, North Australia (TV. T. Bednall). This shell is remarkable from its having two strong keels on the last whorl, and also on account of its uniform dark-brown colour. HELIX (RHAGADA) BORDAENSIS, n. sp. (Plate XL. fig. 3.) Shell widely and deeply umbilicated, lenticular, moderately thin, very strongly and irregularly obliquely flexuously corrugated, the corrugations becoming larger and more elevated towards the middle of the whorls, cretaceous, white; spire depressed, apex obtuse; sutures very strongly impressed and crenated ; whorls 5, nearly flat, the last depressed and strongly keeled above the periphery, not descending in front, slightly keeled around the umbilicus ; aperture oblique, semilunar; outer lip simple; columella very slightly expanded; margins united by a thin callus. Diam. maj. 8, min. 7, aft. 3\ lines. Hab. Cape Borda, Kangaroo Island, South Australia (TV. T. Bednall). This remarkable shell exhibits a somewhat similar sculpture to H. silveri, Ang. (P. Z. S. 1868, p. 275), and II. kooringensis, Ang. (P. Z. S. 1877, p. 33) ; but it differs from both those species in having the raised corrugations more numerous and elevated, displaying at the sutures and on the keel an elegant frilled appearance. It is also smaller, flatter, has a wide perspective umbilicus ; and the corrugated ridges show here and there a tendency to bifurcate. EXPLANATION OF PLATE XL. Fig. 1. Voluta (Aulica) bednalli, p. 418. ' 2. Murex (Pteronotus) bednalli, p. 418. PROC. ZOOL. Soc-1880, No. XXVIII. 28 |