"OUR information concerning the earliest inhabitants of Japan is alike scanty and unreliable. At different spots in Yezo and the Kurile Islands excavations are found from three to six feet deep, with a length or diameter of fifteen to twenty feet; these he in groups, numbering as many as one thousand, and are attributed by the Ainos to a people called Koro-pok-guru, meaning "people having excavations", or "cave-dwellers", or to the Ko-bito (dwarfs), who are said to have inhabited the island before the Ainos and to have been exterminated by them. These holes were probably covered with a roofing of branches on which earth was laid. Excavations in their neighbourhood have brought to light potsherds and stone arrows, a fact which is the more remarkable, as the Aino seem never to have learnt the art of making pottery, which they do not even now possess. On the other hand, a few centuries ago they made use of stone arrowheads; these were later replaced by points of bamboo, which are both more easily made and better suited to hold the poison which they employ in hunting.
Nothing is known as to the origin of the Koro-pok-guru or of the Ainos; apparently both peoples immigrated from the north at an early period; the Ainos at any rate advanced as far as the northern half of Hondo, and perhaps even farther south. Some authorities consider the Ainos a Mongolian, others a Polynesian, people. Dr. E. Baelz places them among the Caucasian races, and believes them to have been related to the Mujiks, the peasants of Great Russia; the resemblance, at any rate in advanced years, is certainly remarkable. In this case we must consider the Ainos as members of a greater continental race, which migrated to Japan in prehistoric times and was gradually driven further northward by later arrivals, ultimately crossing into Yezo by the Tsugaru Strait. There are probably twenty thousand of them in Yezo, the southern part of Sakhalin, and in the Kurile Islands. Where their race has maintained its purity, their civilization is scarcely higher than it was at the time when they first came in contact with the Japanese.
The origin of the Japanese is also wrapped in mystery. The attempt to solve the problem from the anthropological side, and to consider the modern Japanese as a mixed people consisting of Ainos, Korean, Chinese, and Malayo-Chinese elements may be said to have been successful, in so far as all these races have undoubtedly contributed to the formation of the nationality now inhabiting Japan; but no proof has been brought forward to show to which of these races the main body of those immigrants belonged, who probably made their way into Japan long before the seventh century B.C."