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Show 376 MR. E. A. S M I T H O N T H E [Apr. I», several of his own interesting discoveries. The remaining portion was obtained from the Rev. W . Deans Cowan, and was collected by him in a more southern part of the island than that visited by Mr. Johnson. It also contains several very interesting forms, notably the species of Vitrina previously referred to, and the Bulimus nigrilineatus of Reeve, belonging to a section (Rhachis) of that immense group of laud-snails which was hitherto unknown in Madagascar. A. GASTROPODA. CYCLOSTOMA MACAREJE, var. Hab. Betsileo (Cowan). The typical form of this species, described by Petit, was originally collected in the south part of Madagascar, near Saint Augustin. The more northern variety from Betsileo is rather more coarsely sculptured, and has a distinct peripherical black zone, and sometimes a broader but less distinct one on the upper part of the last whorl. CYCLOSTOMA BETSILEOENSE, sp. nov. (Plate XXI. fig. 2.) Shell umbilicated, turbinate-globose, thinnisb, finely spirally lirate, encircled with two more prominent white keels, one at the middle of the body-whorl, and the other above, decussated by close lines of growth ; cinereous (except the reddish spire), copiously striped longitudinally with a brownish colour, with a few spiral purple-black lines and zones, one just beneath the central white carina, broader than the rest, and a rosy stripe outside the labrum. Whorls 5|, separated by a narrowly channelled suture, which is beautifully clathrated by the lines of growth. Two nuclear whorls smooth, convex, forming an obtuse apex ; the rest convex, but appearing a little angular at or a little above the middle, where the upper carina is situated. The visible spiral threads are six in number on the antepenultimate whorl, about twelve on the penultimate (including the two white keels), and nearly double the latter number upon the upper half of the body-whorl, the lower part having as many as thirty-two to thirty-five, those around the umbilicus being a trifle coarser than the rest, the interstices being everywhere decussated by the lines of growth. The spiral lineation is constant in three out of five examples, is chiefly confined to the last whorl, and is most conspicuous within the aperture when the shell is held up to the light. There are two lines above the upper white keel, two between it and the lower one, and about six beneath the latter, the uppermost being much broader than the rest. Aperture subcircular, chestnut within, very dark towards the outer lip, showing the external lines and bands, a little higher than wide. Peristome acute, white on the columellar margin, only narrowly reflexed, flatly and more widely expanded on the right or outer margin, pink, except at the upper part towards the suture. Greatest diameter 25 millim., height 25. Hab. Betsileo (Cowan). In some respects C. pulchellum of Sowerby approaches this species. |