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Show 38G MR. R. B. WATSON ON MADEIRAN MOLLUSKS. [Mar. 18, Inner Up reflected on the pillar, leaving behind it a narrow but deepish umbilical chink; carried across the belly by a distinct callus, the edge of which projects free from the body-whorl. The two lips meet at somewhat more than a right angle. Sh. M. 6. 5. 4. 3. 2. 1. L. ...*071 *029 *031 *019 *011 *006 *003 *001 B *039 *024 *025 *036 *026 017 '009 *003 Hab. Funchal Bay, 50 fathoms. Of this species I have found only one specimen, and it probably a dead shell, though perfectly fresh. It may be a true Madeiran species ; but I confess I should not be surprised were it to prove a Hydrobia introduced in ballast. In the mean time I have put it here among the Rissoce, believing that it is a new species, and perceiving nothing to exclude it from such fellowship. RISSOA GLABRATA, von Muhlfeld. (Plate XXXVI. fig. 24.) Not in M'Andrew's list. Hab. Gorgulho, shore ; Seixal, shore ; Santa Cruz, shore ; Ponta de Sao Lourengo, shore and 25-45 fathoms ; Piedade (Canigal), 25-35 fathoms. M y specimens, from deep water, of this species are very few. It lives abundantly on the shore beneath sheltered stones below high-water mark. In spite of its smallness it is not difficult to find, its white colour making it conspicuous on the black lava-stones of the beach. It is best got by clearing off the loose upper shingle till one reaches the less movable (but not very deep-lying) under layers, where one also finds R. picta, R. Leacocki, Odostomia turrita, Pe-dipes afra, Marinula (Auricula) cequalis, Lowe, Melampus exiguus, Lowe, and other shells. Of the animal, Baron do Castello de Paiva, in his ' Monographia Molluscorum Insularum Maderensium,' says " Corpore toto albo, pellucido, tentaculis brevissimis, pede oblongo." His "var. a. duplo minor " may, I think, be suppressed. A difference of form, however, such as he alludes to as " Subvar. Testa minus ampla . . . apertura strictiore" is found, dependent on the greater contraction of the outer lip. From the description (probably) and from the figure (certainly) of R. (Cingula) balteata I infer that Signor Manzoni has made a new species out of the Atlantic form of R. glabrata*, needlessly as I believe-an opinion supported " certainly " by Mr. Gwyn Jeffreys, who has examined Signor Manzoni's specimens of R. (Cingula) balteata. Mr. M'Andrew, from whom Signor Manzoni procured bis specimens, has kindly sent m e three examples of this species. Of these three, two are R. glabrata, and one is m y species R. lincta. I should have preferred suppressing that name of mine and adopting R. balteata as perhaps intended for it, if it had been possible to take the description and, still more, the figure of that species as in any way applicable to m y R. lincta. * H e gives R. glabrata, Miihl., indeed, as found in Madeira, but he does this only as quoting from Baron de Paiva, who refers for it to me. |