| OCR Text |
Show 1869.] MR.W. T. B L A N F O R D O N N E W MOLLUSKS. 445 ing the recent expedition to Yunan. They will be figured, and previously described species enumerated, in Dr. Anderson's full account of his journey, together with his other numerous novelties. 1. PALUDINA BENGALENSIS, Lam., var. DIGONA(VC1 P. DIGONA). Testa P. bengalensi persimilis, sed decussatim striatula, anfractibus superioribus juxta suturam angulatis; ultimo biangulato, et supra et infra peripheriam, angulis singulis fasciis fuscis spiralibus congruentibus, zona tertia intermedia, aliis basalibus, lineis an-gustioribus spiralibus interdum interjectis. Long. 23^-32 mm., diam. 17^-23; apert. 13-17\ longa, 10|- 14| lata. Hab. in valle fluminis Iravadi circa Ava, Bhamo, &c. Merely a variety of P. bengalensis, and passing insensibly into the type in Assam, and into the var. balteata, Bs. (P. doliaris 1 Gould), in Sylhet. If, however, P. microgramma, v. Martens, P. sumatrensis, Dkr., and similar allied varieties be distinguished by a particular name, this form should also be so, and may in that case be called P. digona. It is perfectly intermediate between P. bengalensis, Lam., and P. oxytropis, Bs. 2. PALUDINA DISSIMILIS, Miill., var. DECUSSATULA (vel P. DECUSSATULA). Testa imperforata, conoideo-ovata, tenuiuscula, olivacea, fascia pallida subperipheriali in anfractu ultimo plerumque signata, sub-glabra, striis incrementi et lineis subconfertis flexuosis spiralibus decussata. Apex acutus; sutura mediocriter impressa. Anfr. 6-7, convexi, ultimus tumidior. Apertura subovata, intus lactea. Peristoma tenue, nigrum. Operculum corneum, crassum. Long. 25, diam. 17-g mill.; apertura 13 longa, 10^ lata. Hab. Ava. Nearer to the variety preemorsa of Benson than to any other Indian form. It is distinguished by its fine decussating striation. The Paludinee of British India, like most of the freshwater shells, are in endless confusion-a state which has certainly not been removed by the work of Von Frauenfeld aud Reeve. I fully concur with the remarks of Von Martens (Malakozoologische Blatter, xiii. p. 98) as to the forms figured in Reeve, which are undistinguishable as species from P. dissimilis of Miiller; indeed I am inclined to go much further, and to class such forms as P. crassa, Hutton, and P. preemorsa, Bens., as varieties also, though they are sufficiently distinct to deserve varietal names. The form now described is equally deserving of distinction. 3. MELANIA IRAVADICA, sp. nov. Testa elongato-turrita, tenuis, fusco-olivacea, decollata. Anfr. circa 7, primi erosi, 3-4 superstites convexi, superi seriebus duabus spiralibus nodorum conferlorum circumdati, ultimus spiraliter liratus, nodis fere vel omnino obsoletis. Apertura rhomboideo- |
