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Show i895.] BOBNEO AND NEIGHBOURING ISLANDS. 125 78. CYCLOTUS LINITUS, Godwin-Austen. Cyclotus linitus, Godwin-Austen, Proc. Zool. Soc. 1889, p. 345, pi. xxxvi. fig. 3. Hab. Mount Rabong, West Sarawak. Some of the specimens from this locality are larger than the types from Busau, being 10 millim. in their greater diameter. With the exception of the apex, they are entirely coated with the thick earthy deposit, which is possibly to some extent protective. The body-whorl descends in front, and is slightly detached from the penultimate at the aperture. 79. HELICINA USUKANENSIS, Godwin-Austen. Helicina usukanensis, G.-A. Proc. Zool. Soc 1889, p. 352, pi. xxxix. fig. 7. Hab. Mengalun Island, Usukan Island, Banguey Islaud, Man-tangak Island, and Palawan ; also Sibutu and Bilatan, Sulu Islands (A. Everett). The specimens from Sibutu and Bilatan were at one time supposed to belong to H. contermina, Kobelt 2 That species, judging from the description, appears to be somewhat more globose, and the keel is said to be thread-like ("carina filiformi"). Perhaps a comparison of specimens, however, may yet show that they really are the same as that species. I have no hesitation in placing all the specimens from the above localities under H. usukanensis, although there are slight differences in size and the colour is variable. It may be uniformly yellowish or pinkish red, but the keel is always whitish, and a narrow reddish zone beneath the carina is more or less visible in most specimens. 80. GEORISSA EVERETTI. (Plate IV. fig. 15.) Testa turbinata, imperforata, rufescens, lineis obliquis minute decussata; anfractus 4, perconvexi, primus Icevis, globosus, ultimus antice subdescendens ; apertura rotunde ovata ; peristoma tenue, marginibus callo tenui junctis, columellari pallido, reflexo. Longit. 2 millim., diam. 1^ ; apertura 1 longa, ^ lata. Hab. Rumbang, W . Sarawak. Only a single specimen of this pretty species was collected by Mr. Everett. It is distinguished from all the other Bornean species by the decussation of the surface, formed by the minute curved lines of growth being crossed by others obliquely sloping in the opposite direction. Under a powerful lens the points of intersection appear somewhat granulous. 81. GEORISSA BANGUEYENSIS. (Plate IV. fig. 16.) Testa turbinata, rufescens, fere Icevis; anfractus 4, perconvexi, sutura prof unda sejuncti, lineis incrementi obliquis substriati, primus subglobosus ; apertura oblique semicircularis ; peristoma 1 Ann. Mag. Nat. Hist. 1894, vol. xiii. p. 59, pi. iv. figs. 6, 6 a. |