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Show 244: ISLAND LIFE. [PART II. There is another reason for the very slight amount of pe~uliarity presented by the fauna of the Azores as compared :WI~h many other oceanic islands dependent on its comparative .. y recent origin. The islands ~hemselves may be of consid~rable antiquity since a few small deposits, believed to be of Mwcene age, hav: been found on them, but there can be little d~ubt that their present fauna, at all events as concerns the birds, had its oriain since the date of the last glacial epoch. Even now icebe;as reach the latitude of the Azores orily a little to 0 . the westward, and when we consider the proofs of extensive ice-action in North America and Europe, we can hardly doubt that these islands were at that time surrounded with pack-ice, while their own mountains, reaching 7,600 feet high in Pico, would almost certainly have been covered with perpetual snow and . have sent down glaciers to the sea. rrhey might then have had a climate almost as bad as that now endured by the Prince Edward Islands in the southern hemisphere, nearly ten degrees farther from the equator, where there are no land-birds whatever althouah the distance from Africa is not much greater ' 0 than that of the Azores from Europe, while the vegetation is limited to a few alpine plants and mosses. This recent origin of the birds accounts in a great measure for their identity with those of Europe, because, whatever change has occurred must have been effected in the islands themselves, and in a time limited to that which has elapsed since the glacial epoch passed away. Insects of the Azores.-Having thus found no difficulty in accounting for the peculiarities presented by the birds of these islands, we have only to see how far the same general principles will apply to the insects and land-shells. The butterflies, moths, and hymenoptera, are few in number, and almost all seem to be common European species, whose presence is explained by the same causes as those which have introduced the birds. Beetles, however, are more numerous, and have been better studied, and these present some features of interest. The total number of species yet known is 212, of which 175 are European; but out of these 101 are believed to have been introduced by human agency, ,leaving seventy-four really indigenous. Twenty-three of these indigenous species are not ('J1AP. XIT.] THE AZORES. 245 found in an.y of tho other Atlantic islands, showing that they have been mtroduced directly from Europe by causes which have acted more powerfully here than farther south. Besides t~ese there are th~rty-six species not found in Europe, of which nmeteen are natives of Madeira or the Canaries three are American, and fourteen are altogether peculiar to ~he Azores. These latter are mostly allied to species found in Europe or in the other Atlantic islands, while one is allied to an American species, and two are so distinct as to constitute new genera. The following list of these peculiar species will be interesting:- CARABJDlE. Anchomenus aptinoides .... .. Allied to a species from the Canaries. Bembidium hesperus ......... Allied to the European B. lretwn. DYTISCIDlE. A gabua godmanni ............ Allied to the European A. dt'spar. COLYDIIDM. Tarphius u:ollastoni ......... A genus almost peculiar to the Atlantic islands. ELATEIUDlE. IIete1·oderes azoricus ..... .... Allied to a Brazilian species. Elastrus dolos~ts ....... ........ Belongs to a peculiar Madagascar genuf:> I MELYRJD1E. A ttctlus rniniaticolUs ......... Allied to a Canarian species. RHYNCOPHORA. Phlreophagus variabilis ...... Allied to European and Atlantic species. Acalles d1·oueti ... ............. A Mediterranean and Atlantic genus. Lapa1·oce1·us azoricus ........ Allied to Madeiran species. Asynonychus godrnanni .... A peculiar genus, allied to Brachyderes, of the south of Europe. Neocnernis occidentalis ...... A peculiar genus, allied to the European genus Strophosornus. HETEROMERA. IIelops azoricus ............... Allied to H. vulcanus of Madeira. 8'J'APHYLINID1E. .Xenomma rnelanocephala ... Allied to X. jilijo1·me from the Canaries. This greater amount of speciality in the beetles than in the birds may be due to two causes. In the first place many of these small insects have no doubt survived the o-lacial epoch 0 ' and may, in that case, represent very ancient forms which have |