Alaska and the opposite parts of Asia hold, in all probability, the key to the problem of the peopling of America. It is here, and here alone, where a land of another continent approaches so near to America that a passage of man with primitive means of navigation and provisioning was possible. All the affinities of the American native point toward the more eastern parts of Asia. In Siberia, Mongolia, Tibet, Manchuria, Formosa, and in some of the islands off southeastern Asia, living remnants of the same type of man as the American aborigines are to this day encountered, and it is here in the farthest northwest where actual passings of parties of natives between the Asiatic coast and the Bering Sea islands and between the latter and the American coasts have always, since these parts were known, been observed and are still of common occurrence. With these facts before them, the students of the peopling of this continent were always drawn strongly to Alaska and the opposite parts of Asia; but the distances, the difficulties of communication, and the high costs of exploration in these far-off regions have proven a serious hindrance to actual investigation. As a result, but little direct, systematic, archeological or anthropological (somatological) research has ever been carried out in these regions; though since Bering's, Cook's, and Vancouver's opening voyages to these parts a large amount of general, cultural, and linguistic observations on the natives has accumulated. For these observations, which are much in need of a compilation and critical analysis, science is indebted to the above-named captains; to the subsequent Russian explorers, and especially to the Russian clerics who were sent to Alaska as missionaries or priests to the natives; to various captains, traders, agents, miners, soldiers, and men in collateral branches of science, who came in contact with the aborigines; to special United States Government exploratory expeditions, with an occasional participation of the Biological Survey and the Smithsonian Institution, such as resulted in the fine "Corwin" reports and the highly valuable accounts of Leffingwell, Dall, Nelson, and Murdoch; to the separate pieces of scientific work by men such as Gordon and Jennes; and to Jochelson and Bogoras of the Jesup exploring expedition of the American Museum. As a result of all these contributions, it may be said that there has been established a fair cultural and linguistic knowledge of the Aleut, the Eskimo, and the Chukchee, not to speak of the Tlingit, consideration of which seems more naturally to fall with that of the Indians of the northwest coast.