together with many northern birds common to both continents. Yet a few Palearctic forms, not known in other parts of the sub-region, appear here. These are Budytes flava, Phylloscopus kennicottii, and Pyrrhula coccinea, all belonging to genera not occurring elsewhere in North America. Considering the proximity of the district to North-east Asia, and the high probability that there was an actual land connection at, and south of, Behring's Straits, in late Tertiary times, it is somewhat remarkable that the admixture of Palearctic and Nearctic groups is not greater than it is. The Palæarctic element, however, forms so small a portion of the whole fauna, that it may be satisfactorily accounted for by the establishment of immigrants since the Glacial period. The great interest felt by ornithologists in the discovery of the three genera above-named, with a wren allied to a European species, is an indication that the faunas even of the northern parts of the Nearctic and Palæarctic regions are, as regards birds, radically distinct. It may be mentioned that the birds of the Aleutian Isles are also, so far as known, almost wholly Nearctic. The number of land-birds known from Alaska is 77; and from the Aleutian Isles 16 species, all of which, except one, are North American. Reptiles.-These are comparatively few and unimportant. There are however five snakes and three tortoises which are limited to Canada proper; while further north there are only Amphibia, represented by frogs and toads, and a salamander of the genus Plethodon. Fishes.-Most of the groups of fresh-water fish of the Nearctic region are represented here, especially those of the perch, salmon, and pike families; but there seem to be few or no peculiar genera. Insects.-These are far less numerous than in the more temperate districts, but are still tolerably abundant. In Canada there are 53 species of butterflies, viz., Papilionidæ, 4; Pieridæ, 2; Nymphalidæ, 21; Satyridæ, 3; Lycænidæ 16; and Hesperidæ 7. Most of these are, no doubt, found chiefly in the southern parts of Canada. That Coleoptera are pretty numerous is shown, by more than 800 species having been collected on the |