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Show 1891.] LAND-SHELLS P R O M THE SAMUI ISLANDS. 155 ram valde constrictus, turn campanulatus, sublcevigatus, in parte Icevigata obtuse cristatus. Apertura diagonalis, subcircu-laris; peristoma duplex, externum sat expansum, internum continuum, valde porrectum incrassatulum, superne et basi effusum et subcanaliculatum. Diam. maj. 2*25, min. 1*75, alt. V2 millim. Evidently a near ally of the small Perak species, such as A. micro-discus, m., but at once distinguished by the peculiar grooves near the upper insertion and at the base of the peristome. 29. DIPLOMMATINA (SINICA) SAMUIANA, sp. nov. (Plate XVI. figs. 18, 19.) T. dextrorsa, elongate ovato-conica, confertim costulata, cornea. Anfr. 7, moclice convexi, superi 5 spiram subregulariter conicam efficientes; penultimus magnus ; ultimus angustior, distortus, initio constrictus, antice aseendens. Apertura verticalis, subcircularis; peristoma duplex, externum expansum, superne interruptum, internum incrassatulum, sat porrectum, basi columella angulum distinctum formans. Lamella columellaris humilis, palatalis longiuscula, subhorizon-talis, supra columellam conspicua. Alt. 2*5, diam. 1*33 millim. Fam. PUPINID^. 30. PUPINA ARTATA, Bens. 31. PUPINA PALLENS, sp. nov. (Plate XVI. figs. 27, 28.) T. conoicleo-ovata, Icevis, nitens, pallide corneo-brunnea. convexiusculi ; ultimus sat distortus, supra aperturam applanatus, antice breviter aseendens. Apertura paullum retrorsum incli-nata, circnlaris; peristoma expansiusculum, haud reflexum, margo externus ad insertionem attenuatus, recedens cum lamella parietali triangulari valida canalem superum formans, bascdis et columellaris incrassati et dilatati. Canalis inferus horizontalis, postice in foramen subcireulare desinens. Alt. 8, diam. 5*5 millim. This somewhat difficult form agrees in size with P. arula, Bens., of Perak and Tenasserim, but differs in the more obtuse spire, the more distorted last whorl, and consequently the aperture placed more to the right and protracted at the base, the thinner outer peristome, the broader columella, the broad triangular parietal lamella, and the narrower lower incision. Fam. HYDROC^ENIDJ;. 32. GEORISSA MONTEROSATIANA, Nev. et G.-A. Subsp. nov. SAMUIANA.-Minor, anfr. magis convexis. Alt. 2*5, diam. 1*5 millim. A flight modification of the Perak type. |