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Show 366 MR. G. R. CROTCH ON AZOREAN COLEOPTERA. [Mai*. 28, Elastrus dolosus, which has congeners only in Madagascar, but external form simulates some Cape Elaters so as to be undistinguishable except by a close examination. This Madagascar connexion is found also in the Cape de Verde Islands, which have two or three species in common with it. To sum up these affinities numerically, we find that of the 213 species 168 are European, 18 Atlantic, and 23 peculiar-or that 168 are common to Europe, 140 to Madeira, and 114 to the Canaries. The proportions of the families vary a little from those observed in Madeira and the Canaries. . ,T , , n Azores. Mad. et Can. Braehelytra 48 215 Necrophaga 38 219 Rhynchophora 27 282 Geodephaga 27 188 Priocerata 16 135 Cordylocerata 16 64 Heteromera 15 172 Philhydrida 8 29 Pseudotrimera 7 30 Eucerata 5 22 Phytophaga 3 64 The most notable displacements here are the very great absence of Phytophaga, the lowering of the standard of Rhynchophora, always much the largest group in the other islands, and the singular paucity of Heteromera. The large development of Necrophaga and Braehelytra is due to their containing many introduced species. All this seems to show that, on the hypothesis of a connected continent, the fauna of the Azores was drawn from a much more northern source than that of the other islands. This is particularly evinced by the absence of Heteromera. The paucity of water-beetles, notwithstanding their rainy condition, is less easily accounted for; but the same occurs in Madeira, where previously to the destruction of the forests there must have been water enough, and yet even the universal Gyrinus dejeani does not occur there. A more restrained type of fauna is indicated by the solitary representatives of the Atlantic genera (Tarphius &c), which further south develope numerous forms in each island; it may, indeed, have been that the Azores formed almost the western boundary of land in this direction. This brief sketch will show how full of interest the subject is, and how much yet remains to be done even in the groups apparently most explored. I shall now enumerate in order the 213 species at present known as inhabitants of these islands, and describe those which appear to be new, reproducing the novelties already described by M M . Drouet and Morelet. 1. CALOSOMA AZORICUM, Heer. Under stones in S. Miguel, Terceira, and Santa Maria, but rarely. This agrees precisely with the specimens recorded by Mr. Wollaston from Lanzarote in the Canaries, and forms the only link between |
