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Show 1875.] REV. 0. P. CAMBaiDGE ON NEW SPiiCIES OF ERIGONE. 323 a reddish brown, densely pubescent epidermis disposed in numerous fine spiral lines crossed by strise of growth. Whorls 6, convex, gradually increasing, the last forming more than one half, the first two usually bare of epidermis and ornamented with a rugosely costellate sculpture. Suture rather deep. Aperture oval. Outer lip white, a little thickened and everted. Columella thickened and broadly reflected over the very deep umbilical perforation. Length 17, breadth 8, height of aperture 6 millimetres. Venezuelan Guiana (R. Tate). This variety is rather smaller than the type, and is apparently more densely pubescent; but the latter character may be partly due to the state of preservation of the shells. It would appear also that the cancellation and more particularly the sculpture of the apex are more strongly marked than in the type. The nearest known relative of B. constrictus is, I believe, a shell described by me as Bulimulus pilosus (Amer. Journ. Conch. 1870, p. 310). That shell is of a lighter colour, is rather smaller, and has a less-dense pubescence. When aestivating, B. constrictus forms a white calcareous epiphragm, which does not happen with B. pilosus. The shape of both species is almost exactly that of B. oblongus in miniature. They seem to find their nearest allies in St. Helena, having points of resemblance to B. digitalis and B. helena oi that island. The character of the apex is very peculiar; and I am informed by Mr. T. Bland that he has detected a somewhat similar feature in other Bulimi from the central portions of the American continent. The apex of B. pilosus is costellate; in B. constrictus it is often, though not always, somewhat rugose: these differences seem to be principally due to the more or less eroded state of that part. It was on account of the very considerable differences between these shells and those ranked as Bulimulus that I formerly referred them to Buliminus; but it is possible that they belong to neither of those genera, but form a separate group under the genus Bulimus (as restricted in Albers, ' Die Heliceen,' 2nd ed.). That group may retain the name of Rhinus (Albers, p. 223), but should perhaps be removed from Bulimulus, and placed, along with Pachnodus (op. cit. p. 230), or at least a part of that section, under Bulimus, adding to the definition of Bhinus, after "anfr. 6-7," the words "apice costellata vel rugoso-costellata." 3. On some new Species of Erigone. By the Rev. O. P. CAMBRIDGE.-Part II. [Eeceived March 31, 1875.] (Plate XLIV.) The following pages comprise descriptions of nine species of Erigone additional to those described in a former paper (p. 190, supra), and all received from various localities in France. While, however, those described in the former paper were, with two exceptions, of 21* |