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Show 1871-] MR. HARPER PEASE ON POLYNESIAN LAND-SHELLS. 453 To the above genus I add the following new species:- PITYS ATIENSIS, Pse. T. orbicularis, tenuiuscula, aperte umbilicata, radiatim confer subarcuatim costulata, supra et infra fiavido et rufo tessellato-strigata ; spira vix elevata, apice obtuso, sutura bene impressa anfr. 5, convexi, ultimus ad peripheriam basinque rotundalus apertura subcircularis, obliqua; perist. simplex, rectum. Diam. 3, alt. If mill. Hab. Insula Atiu. P. modicella (Fer.) is the nearest allied species, from which it differs in being more openly umbilicate, the spire more elevated, and the colours differently disposed. PITYS ROTELLINA, Pse. T. planorboidea, solidiuscula, anguste umbilicata, tenuissime radiatim striatula, supra planiuscula, vix elevata, apice depresso: anfr. plano-convexi, ultimus ad peripheriam basinque rotundatus ; apertura obliqua, lunaris, subcompressa, angusta; paries aperturalis lamella unica intrante munitus ; perist. simplex, rectum ; fiavido et rufo alternatim undique strigata. Alt. 1, diam. 2 mill. Hab. Insula Aitutake. PITYS IMPERFORATA, Pse. T. imperforata, vel punctiformi-perforata, orbicularis, tenuiuscula, radiatim confertim et tenuissime costulata, flavido et rufo radiatim tessellato-strigata, strigis ad peripheriam basinque flexuosis; spira plano-convexa, apice obtuso, sutura impressa; anfr. 6, plano-convexi, strictim et lente accrescentes, fere eequaliter, ad peripheriam rotundatus, basin plano-convexus ; apertura obliqua, lunaris, lamellis 4-5 munita, 2 in pariete aperturali, in margine basali; perist. simplex; columella callosa, vix eversa. Diam 4, alt. 2 mill. Hab. Insula Aitutake. Nearest allied to P. rotula, Jacq. It has more whorls, is distinctly radiately ribbed, and the reddish stripes extend over the base in zigzag shape. PITYS RORATONGENSIS, Pse. T. orbicularis, tenuiuscula, nitidiuscula, aperte umbilicata, radiatim conferte subflexuoso-costulata, fiavido et rufo radiatim alternatim strigata, strigis ad peripheriam basinque undulatis; spira elevata, apice depresso, sutura bene impressa; anfr. 4g, rotundato-convexi, leviter accrescentes, ultimus ad peripheriam basinque rotundatus; apertura obliqua, lunaris, lamellis 4 munita, 2 in pariete aperturali, 2 dentiformibus in margine basali; peristoma columellaque simplicia. Diam. 2\, alt. 1 mill. Hab. Insula Roratonga. |