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Show 372 MR. R. B. WATSON ON MADEIRAN MOLLUSKS. [Mar. 18, Mouth almost disconnected from body-whorl; a very perfect oval, lying a little transverse to the length of the shell; scarce contracted across the belly, and hardly at all narrowed towards the upper corner; open; especially patulous below ; surrounded by a heavy margin, with a pad at upper corner. Outer lip enormously thrown out, from the form of the mouth, the thickness of the shell, and above all, by the great projection of the labial varix. This varix is thick, white, and scored by the longitudinal and spiral striolations, which, however, do not appear on the lip front. It is sinuated above, but not channelled below. At its junction with body-whorl it leaves a deep sharp narrow chink. It is roundly flattened on its front surface, and edged internally with a narrow, blunt, and slightly projecting flange, which sweeps round the whole mouth. This flange sometimes fails to project beyond the plane of the surface, and then merely forms a kind of shelf; sometimes it is followed deeper within tbe mouth by another shelf. Outside of this flange a slight marginal edging sweeps round parallel to the extreme outline of the varix. Pillar-lip is formed internally by the labial flange, which here becomes a mere shelf, and externally by the marginal edging of the outer lip, which, sweeping round to the point of the pillar, splits off jaggedly from the labial varix, forms a sharp, narrow, and reflectedly projecting edge between the mouth and the huge and deep umbilicus, and hardly touches the body-whorl except to bury the umbilical ridge and to unite itself to the pad of the outer lip. Sh. M. 5. 4. 3. 2. I. L *073 *026 *039 *014 *01 *006 *005 B 055 *026 046 *045 *027 '022 -01 Hab. Gorgulho shore; Santa Cruz, 10-15 fathoms; Machico, 10-15 fathoms ; Monte de Piedade (Canigal), 15-35 fathoms ; Ponta de Sao Lourenco, 25-15 fathoms ; Porto Santo, up to 50 fathoms. Mr. Gwyn Jeffreys says of this species, " A very beautiful and new species, allied to R. costata, Adams." The basal ridge and fossae and the high, sharp, narrow ribs have some suggestion of a resemblance; but the short hunchy form (whence I have named it), the smooth surface, and prodigious umbilicus are far more elements of contrast. I doubt its being a Rissoa; but I have unfortunately never found the living animal, nor even met with the operculum. RISSOA MACANDREWI, Manzoni. (Plate XXXIV. fig. 8.) Hab. Funchal Bay, up to 50 fathoms ; Cruz Point, 50 fathoms; Canary Islands (Manzoni, from M'Andrew's dredgings). In some of its forms R. macandrewi greatly resembles some forms of R. canariensis; but the spire rises more in steps, the last three whorls are less attenuated, the ribs are wider-set, are broader, and fewer; the spiral scratchings are much more distinct. The heavy white labial rib and the absence of the brown stain either on this rib or on the tip of the apex are very distinctive. Manzoni's figure |