celebrated for its power of ejecting a terribly offensive liquid, the odour of which is almost intolerable. The skunks are nocturnal animals, and are generally marked, as in the species represented, with conspicuous bands and patches of white. This enables them to be easily seen at night, and thus serves to warn larger animals not to attack them. To the left is the curious little jumping mouse (Jaculus hudsonius), the American representative of the Palearctic jerboa. Climbing up a tree on the left is the tree porcupine (Erethizon dorsatus), belonging to the family Cercolabida, which represents, on the American continent, the porcupines of the Old World. In the background is the elk or moose (Alces americanus), perhaps identical with the European elk, and the most striking inhabitant of the northern forests of America, as the bison is of the prairies. Birds.-Although the Canadian sub-region possesses very few resident birds, the numbers which breed in it are perhaps greater than in the other sub-regions, because a large number of circumpolar species are found here exclusively. From a comparison of Mr. Allen's tables it appears, that more than 200 species are regular migrants to Canada in the breeding season, and nearly half of these are land-birds. Among them are to be found a considerable number of genera of the American families Tyrannidæ and Mniotiltidæ, as well as the American genera Sialia, Progne, Vireo, Cistothorus, Junco, Pipilo, Zonotrichia, Spizella, Melospiza, Molothrus, Agelaus, Cyanura, Sphyrapicus, and many others; so that the ornithology of these northern regions is still mainly Nearctic in character. Besides these, it has such specially northern forms as Surnia (Strigidæ); Picoides (Picidæ); Pinicola (Fringillida); as well as Leucosticte, Plectrophanes, Perisoreus, and Lagopus, which extend further south, especially in the middle sub-region. No less than 212 species of birds have been collected in the new United States territory of Alaska (formerly Russian America), where a humming-bird (Selasphorus rufus) breeds. The great majority of these are typically American, including such forms as Colaptes, Helminthophaga, Siurus, Dendraca, Myiodioctes, Passerculus, Zonotrichia, Junco, Spizella, Melospizpa, Passerella, Scoleophagas, Pediocetes, and Bonasa; |