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Show 1895.] MOLLUSCA OF T H E A N D A M A N AND NICOBAR ISLANDS. 449 Genus DURGELLA. 2. DURGELLA ANDAMANICUS, Nevill MS. (p. 442). I have not seen this species. It is entered in the ' Hand-list.' 10 in the Calcutta Museum (10 in spirit), type Andamans from de Roepstorff, " has been taken for the young of Durgella christi-ance," which is not unlikely to be the case. Genus GIRASIA. GIRASIA, sp. inc. (p. 442). My brother described having found, when he made the ascent of Saddle Peak on North Andaman with Col. Hobday of the G. T. Survey, a large slug-like form resembling this genus. It was done up in leaves, but was accidentally lost before they got into camp. This genus may therefore be sought for by future collectors. Genus PLANISPIRA. 4. PLANISPIRA WIMBERLEYI, n. sp. (p. 442). Locality. Nicobars (de Roepstorff). Shell depressedly orbiculate, narrowly umbilicated, very finely hirsute; sculpture, when this is abraded the surface is covered with minute regular papulation, which is much coarser than that of H. helferi • colour horny grey; spire rounded ; apex rounded; suture impressed; whorls 4, not fully developed, slightly convex ; aperture and peristome probably slightly expanded and reflected. Size: maj. diam. 10*2, min. 8-9 ; alt. axis 5*7 mm. This species is nearest to H. helferi, but may be distinguished by its narrower umbilicus and the great difference in sculpture, and the whorls above are not so flat. This is probably no. 102 of Nevill's 'Hand-list' (p. 76), collected by Ferd. Stoliczka. Planispira helferi, Benson, has only hitherto been found in the Andamans ; the young shell of four whorls and banded I found in Mr. de Koepstorff's collection from the Nicobars; but it might have got among them accidentally, and therefore this new habitat has to be confirmed. Genus SIVELLA. 1. SIVELLA CASTRA, Blandf. A variety is recorded by Nevill, ' Hand-list,' p. 56, from the Andamans and a single specimen is in my collection from Mr. Wood- Mason. The umbilicus is wider than in castra and the apex far flatter. Sculpture quite smooth below, with transverse stria?; whereas castra from typical locality, of same size, has close spiral striation most distinct. There is also a remarkable difference in the suture, the Andaman shell has a fine beading running into it, produced by the sharply defined carinate edge of the shell. I believe this to be only an immature Discus sanis. PROC. ZOOL. Soc-1895, No. X X I X . 29 |