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Show 1894.] LAND-SHELLS FROM THE SAMUI ISLANDS. 149 With all proper hesitation at introducing a new species of genus, the very numerous species of which certainly require some weeding out, I cannot combine this form with any published Macrochlamys. Its nearest ally seems to be M. resplendens, Phil., var. obesior, Mart. (Ostas. Laudschn. p. 72, t. xii. fig. 6), of Siam, which has a slight callosity behiud the peristome ; it is, however, only visible in very adult specimens and but a thin layer, whilst all my specimens of M. limbata show a distinct inner lip, which is repeated several times in the interior of the last whorl. Besides, the Samui form has a wider umbilicus, more convex whorls, equal colouring above and below, and a somewhat darker radial stripe. 7. SITALA INSULARIS, sp. nov. (Plate XVI. fig. 8.) T. semiobtecte et angustissime perforata, conico-turrita, striatula, lineis spiralibus valde confertis decussata, corneo-hyalina. Anfr. 8, planidati; ultimus ad peripheriam acute carinatus, non descendens. Apertura parum obliqua, rotundato-securiformis; peristoma rectum, acutum, margine columellari superne refiexo. Diam. 3*75, alt. 4*75 millim. By the great number of whorls, the regular couical shape, and the very narrow spiral sculpture this species is distinguished from all forms of Sitala known to me. 8. KALIELLA SUBSCULPTA, sp. nov. (Plate XVI. fig. 9.) T. anguste perforata, globoso-conica, tenuis, subtiliter et costulato-striata, corneo-fusca ; spira conoidea, convexis. Anfr. 6, convexi ; ultimus non descendens, basi ad peripheriam obtuse angulatus. Apertura obliqua, late lunaris; peristoma rectum, acutum, margine columellari superne triangulariter refiexo. Diam. 2-9, alt. 2*7 millim. The only Kaliella described from the Malay Peninsula is K. pe-rakensis, G.-Aust., which shows a similar outline, but is more distinctly carinate and only striated; it also has much less convex whorls. The sculpture of our species is similar to that of K. sculpta, Mdff., of Macao, which has otherwise a much lower spire and flatter whorls. 9. HEMIGLYPTA SIAMENSIS (Pfr.). Known from Siam and Tenasserim. The spire of the Samui form is generally more elevated. 10. ARIOPHANTA WEINKAUFFIANA INFLATA, subsp. nov. This variety differs from the Coehin-China type in the less distinct angulation of the periphery and the more convex, almost inflated base of the last whorl. |