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Show 1892.] LAND-SHELLS OF ST. HELENA. 267 peristoma tenuissimum, margine exteriore simplice, haud expanso, columellari supra umbilicum anguste reflexo, tenuiter calloso, in medio plica parva vel denticulo munito. Longit. 17 millim., diam. 7-f ; apertura 7f longa, 4 lata. Var. Testa fusco-cornea, lineis opaco-lacteis tenuibus confertis plus minus irregularibus et interruptis picta, circa medium anfractus ultimi zona pallida cincta. Hab. High Peak, among native vegetation (Turton). Living. This perhaps is the prettiest land-shell occurring in the island, and it is remarkable that it has escaped the notice of most of the explorers and naturalists who have visited and collected at St. Helena. Two specimens, however, have been in the collection at the British Museum for many years. They were received from the Museum of Economic Geology in January 1860, but it is uncertain by whom they were collected. The substance of the shell is extremely thin and fragile and the surface exhibits no other sculpture excepting lines of growth. The colour-ornamentation is variable. In what may be regarded as the typical form the opaque creamy longitudinal markings take the form of broadish irregular wavy stripes, which frequently run into one another, so that they exhibit a more or less zigzag appearance. In other specimeus these broadish stripes are replaced by very numerous and slender lines, which are more or less wavy and sometimes considerably interrupted and broken up. The plait or denticle upon the columella is peculiar, giving to it a subtruncate appearance. B. neglectus, Pfr., B. costatus, Pfr., and some other forms of Peronceus have a somewhat similar plication on the columella, but rather higher up. I have much pleasure in associating this beautiful species with the name of Capt. W . H.Turton. (Section 1) 21. B U L I M U L U S M E L A N I O I D E S (Wollaston). (Plate XXII. fig. 18.) Hab. Diana's Peak, at an elevation of over 2000 feet (Turton). Living. This is very distinct and quite unlike any other known species. It was located by Mr. Wollaston in the genus Subulina on account of the truncation or fold at the base of the columella. This feature, although rather higher up on the columella, is also met with in certain Bulimi from Brazil, as I have already pointed out in connection with the preceding B. turtoni. I therefore am inclined to assign this species rather to Bulimulus than to Subulina, as moreover it bears very little resemblance to any species of that group. 22. TOMIGERUS (?) PEREXILIS, sp. nov. (Plate XXII. figs. 19- 19 6.) Testa dextrorsa vel sinistrorsa, minuta, obtuse pyramidalis, imperforata, albida vel dilute rufescens ; anfractus 5, convex- |