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Show 1891.] LAND-SHELLS F R O M BORNEO. 25 Nanina glutinosa, v. Martens, Preuss. Exped. Ost-Asien, Land-schneck. p. 214 (1867). Macrochlamys glutinosa, Wallace, P. Z. S. 1865, p. 405. Nanina (Xesta) glutinosa, Issel, Ann. Mus. Civ. Genova, vi. p. 392 (1874). Hab. Niah Hills (A. Everett). Mr. Everett collected a fine set of this species, which has a very conspicuous canaliculate groove above the keel of the shell, and this on the upper whorls produces a raised beading at the suture. In the same locality he obtained a beautiful dark madder-brown variety, similar in coloration to X. decrespignyi, which retains exactly the form of the typical shell, and is not separable by any other character. I would designate this as var. rubra. Shell-lobes (Plate V. fig. 6, r.s.l. and l.s.l.) as in Macrochlamys; the right dorsal lobe (r.d.l.) large; the left differs from above and is divided in two parts, of which the anterior is narrow and long, the posterior being very rudimentary. Situated between, there is a very well-defined long tongue-like shell-lobe. The living shell must be very prettily mottled, as the black-spotted integuments of the respiratory sac would show through the glassy thin shell. Mucous gland with an overhanging lobe, the aperture does not extend down to the sole of the foot as shown in pi. xxxv. fig. 6 of m y ' Land and Freshwater Mollusca of India.' Odontophore has plain, unicuspid, triangular-shaped centrals; about eighty of the outer laterals are bicuspid, and those on the side of the radula are verv minute : ml 110 . 14 . 1 . 14 . 110 124 . 1 . 124. Jaw slightly curved on the cutting-edge, with only the slightest indication of a central projection. The generative organs approach nearest to Macrochlamys of the Indian Region, but variation presents itself in the male organ (Plate V. figs. 6 a and 6 b). It is bent upon itself, the kale-sac is short and knob-like, and where the retractor muscle is given off there is a simple bend, with no projection, and doubling together of the tube and the formation of a coil as in so many of the Indian genera and species. The drawings given by Professor Semper of the reproductive organs of Xesta, which include X. citrina and X. mindanaensis, particularly of thelatter, agree with X. glutinosa. As regards the odontophore, it is similar to that of X. citrina in the simple centrals, which I consider to be the type of the genus ; it is also the type of X. mindanaensis. It may be noted that the odontophores of the Indian species X. belangeri, tranquebarica, and maderaspatana differ considerably in their tricuspid form, and will, I think, prove different in other characters \ 1 In the British Museum (Cuming Collection) is a specimen labelled from the Solomon Islands (Hon. Capt. Keppel) named H. capitanea, Pfr. (P. Z. S. 1854, p. 49). It is a young shell, evidently of X. glutinosa, and, I should say, not obtained in the islands quoted. |