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Show 1867.] MR. G. R. CROTCH ON AZOREAN COLEOPTERA. 359 which differs in its construction from all the other specimens of that genus known to us either in the French Museum or in the English collections. This sponge is about 8 inches in height, 2\ inches in diameter at the apex, and 1 h inch at the base, and the body is cylindrical. The parietes of the sponge are of about the same thickness as those of A. speciosum. The primary lines of the skeleton are wide apart, irregular, and run diagonally and flexuously over its surface. The basal end of the sponge is closed and rounded, and one side of it is rather longer than the other, and there is not the slightest indication of its having been furnished with prehensile spicula similar to those of A. speciosum. The attachment of the sponge is partly on one side, in the form of a thick incrustation, and partly close to the base, by a similar patch of thickened tissue. But the most striking and characteristic difference in its structure is in the apical termination of the sponge, which is totally destitute of the great marginal ring that surrounds the oscular area in A. speciosum, the sides and oscular area merging in each other insensibly and without the slightest trace of a boundary line. In this character this species closely resembles the distal extremity of Polymastia mammillaris and other species of that genus, which have not the oscular area confined within a marginal ring. The specimen appears to have been too well washed, as no remains of interstitial spicula could be discovered with a 2-inch lens. The sponge is exceedingly beautiful, and the skeleton-structures appear by the aid of the lens like twisted spun glass. Beside those described above, there is another specimen of Alcyoncellum in the Museum of the Jardin des Plantes, which is also named A. corbicula ; but it differs so much in its structural characters as to render it highly probable that it is a distinct species. It is about 5 inches in height, 2\ or 3 inches across at its apex, and at the base it is 1\ inch in diameter. The base is round and smooth, but the body of the sponge assumes a square form. The texture of the sponge is very much thickened and woolly in appearance, and the spaces in its sides much larger than those in the other specimen designated by the same name. The primary lines of the skeleton are rather flexuous towards the base of the sponge, but they become more regular and straight as they approach its apex. There are no indications of elevated ribs either on the exterior or interior of this sponge. I have had no opportunity of examining its structural peculiarities ; but I have little doubt of their being different from those of the sponge bearing the same name in the French collection. 8. On the Coleoptera of the Azores. By GEORGE II. CROTCH, M.A. (Plate XXIII.) The Azores, though not less interesting, have yet received a far less share of attention, as far as their fauna is concerned, than the |