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Show 390 MR. R. B.WATSON ON MADEIRAN MOLLUSKS. [Mar. 18, sea species obtained by him in the * Porcupine' dredgings in the North Atlantic and Mediterranean. I have accordingly accepted the excellent name which he had already attached to his undescribed specimens. It seems to be the only new species I have found here which has yet been met with in these deep-sea dredgings. Its connexion with R. coriacea, Manzoni, is obvious and interesting. The whole texture of the shells, from their embryonic state onwards, indicates that whatever the place ultimately assigned to the one, must be shared by the other. Manzoni suggests Odostomia as its possible genus; but the untwisted or regular apex negatives that idea. Until something is known of the animal, tbe species may well remain among the Rissoce. To coin a new genus for it at present would only be to multiply an evil which is already well-nigh unbearable. BARLEEIA RUBRA, Mont. I add this species on the authority of Manzoni, who, in his ' Memoire sur les Rissoa des iles Canaries et de Madere,' says he has many specimens from Madeira. For myself, I have not met with it here, and have serious doubts of its existence in Madeira. In addition to the above, the following species have presented themselves. They may belong to the island ; therefore I enumerate them; but m y specimens have, I think, been brought in ballast. They are all dead shells, and were dredged in Funchal Bay. Now, apart from the indigenous land- and freshwater-shells which, drifted out to sea, not unfrequently turn up in the dredge, I have there found, of land-shells quite certainly foreign, the following:- Pisidium amnicum, P'. fontinale,\&r. henslowana, Neritina fluviatilis, Bythinia tentaculata, Valvata piscinalis, V. cristata, Planorbis albus, var. draparnaldi, P. complanatus, Limneea perayra, and Assiminea grayana. Such a list makes me hesitate to accept the following for Madeira. RISSOA MONTAGUI, Payr. One young specimen. This is a fossil species of the Upper Tertiary and a living Mediterranean species, which, beyond the Straits of Gibraltar extends (fide M'Andrew) northwards as far at least as Cape S. Maria, the southern point of Portugal. South of the Straits it seems unknown. RISSOA INCONSPICUA, Alder. One specimen. An Upper-Tertiary fossil, and living (fide Jeffreys) from Norway to the Canaries, including the Baltic and the Mediterranean. My solitary specimen is young and fresh. It may prove to belong to Madeira ; but the species in itself seems to me too questionable to be of much interest, save as a variety of that hopeless polymorphic group which includes half a dozen British and endless foreign species. |