1895.] BORNEO AND XEIGHBOUBING ISLANDS. 101 



rotundatus,haud descendens ; apertura oblique lunata ; peristoma 

 teniie, margine columeUari superne breviter et anguste rejlexo. 

 Diam. mcij. 18 millim., min. 16, alt. 12. 

 Hab. Upper Padas, British North Borneo. 



A transparent, glossy, narrowly perforated shell, without colour- 

 markings, and with only very faint lines of gro\v'th, and here and 

 there very feeble indications of spiral etriation. A dark line, 

 occasioned by stains from the animal and which can be washed 

 away, frequently accompanies the sutui-e. 



3. Xesta thisbe. (Plate II. fig. 4.) 



Testa subglobosa, conoidea, perfoi'ata, ad peniyheriam sidmngidata, 

 rufo-comea, zona angusta pallida, supra rvfo-fmco marqinata 

 circa medium eincta, polita ; spira conve.ve conica, ad ap>icem 

 mediocriter acuta ; anfractus 6, conve.riuscidi, striis incrementi 

 tenuissimis sculpti, xdtimus supra et infra medium suhoiqualiter 

 convexus, ad peripheriam obtuse a-)igulaius ; apertura obliqua, 

 irregulariter lunata ; peristoma tenuisdmum, margine columel- 

 lari sitpra umbilicum breviter dilatato, rejlexo, purpureo. 

 Diam. maj. 26 millim., min. 23, alt. 18. 

 Hab. Mount Eabong, in the south-western part of Sarawak. 

 Differing from X. de crespignii in colour, the more angular body- 

 whorl, and more slowly increasing spire. The periphery is marked 

 by a pale yellow uarro^^• zone, and the rich brown band, which is 

 contiguous with it above, revolves up the spire a short distance. 

 The surface is highly glossy, and, in addition to the delicate lines 

 of growth, faint indications of very fine spiral striation are here 

 and there traceable. In certain positions the incremental striae 

 beneath the suture appear more distinct than upon the rest of the 

 surface. 



4. Hemiplecta densa (Adams & Eeeve), var. eteeetti. (Plate 

 II. fig. 8.) 



In the 'Annals,' 1893, vol. xi. pp. 349, 350, I mentioned the 

 occurrence at Palawan of a very acutely keeled variety of this 

 species. It most nearly resembles that form which is recognized 

 as var. scJmmacheriana. It is, however, a trifle larger and flatter 

 above, the peripheral keel in consequence appearing somewhat 

 more acute. Additional specimens brought by Mr. Everett appear 

 to make it advisable to designate it with a varietal name. I 

 would therefore suggest that it be known as var. everetti. The 

 largest example from the south-eastern part of the island is 

 58 millim. in diameter. 



5. Hemiplegia pe.ictjlta. (Plate II. fig. 7.) 



Testa anguste umbilicata, depresse conica, ad peripheriam acute 

 carinata, mediocriter tenuis, subpellucida, cornea, epidermide 

 pallide olivacea induta, infra suturam et peripheriam pallide v el 

 saturate rufo-nigro marginata ; spira breviter conica ; anfractus 

 5—6, celeriter accrescentes, superne vix convexivscxd,i, inferne 



