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Show 102 ME. E. A. SMITH ON LAND-SHELLS EEOM [Eeb. 5, leviter concavi, striis obliquis irregularibus tenuibus lineisque incrementi oblique curvatis sculpti, ultimus magnus, supra et infra carinam compressus, infra mediocriter convexus, oblique, concentrice, tenuiter sed corrugato-striatus; apertura obliqua, angulato-lunata ; peristoma mediocriter validum, intus anguste incrassatum, ad insertionem supra umbilicum breviter expansum, fuscescens. Diam. maj. 48 millim., min. 39, alt. 25. Hab. Meri, Sarawak (C. Hose). A single specimen was collected at the above locality by Mr. Hose, but a finer example, which may be regarded as the type, was presented to the Museum a year or two ago by Dr. H. Woodward. This fine species does not resemble any of the other known Bornean forms, and is remarkable for the conical spire, the acutely angled body-whorl, and the rapid increase of the volutions. The fine oblique wrinkly striation is also a characteristic feature. It is placed temporarily in Hemiplecta, for when the soft parts are known it may prove to be a dextral form of Dyakia. 6. HEMIPLECTA EGEEIA. (Plate II. figs. 5, 6.) Testa depressa, orbicularis, carinata, anguste umbilieata, fusca, concolor, supra haud nitida, infra nitens; spira depresse conoidalis, ad apicem obtusa; anfractus 6, subplani, lente regulariler crescentes, lineis incrementi tenuibus striati, et supra minutissime corrugati vel suhgranulati, ultimus subacute carinatus, infra carinam convexiusculus, nitidissimus, lineis spiralibus microscopicis sculptus; apertura angulato-lunata, obliqua; peristoma tenue, margine columellari obliquissimo, subarcuato, ad insertionem supra umbilicum breviter dilatato et reflexo, sublivido. Diam. maj. 35 millim., min. 31, alt. 16. Hab. South-west Palawan. The upper surface of this species is of a dull appearance, resulting from the minute granulation or wrinkling. On the contrary, the underside is very highly polished. It differs from H. densa, var. everetti, not only in sculpture, but in the less rapid increase of the whorls, the flatter spire, and narrower umbilicus. The excessively fine concentric stria? upon the lower surface are particularly noticeable within the aperture, where the surface of the whorl is dulled by a filmy deposit. It may be a dextral form of Dyakia. 7. HEMIPLECTA EABONGENSIS. (Plate II. fig. 9.) Testa depresse conica, anguste perforata, tenuis, cornea, apicem versus fuscescens, supra haud nitida, infra sericata, ad peripheriam acute carinata; spira breviter conica, ad apicem obtusa; anfractus 7, vix convexiusculi, lente accrescentes, undique minute granulati, lineisque incrementi obliquis sculpti, supra suturam anguste marginati, ultimus infra medium convexius-cvlus, minutissime corrugatus vel subgranulatus; apertura |