Let us now pass on from the Eurasian northland to what is, zoologically, almost its annexe, North America; its tundra, for example, where the Eskimo live, being strictly continuous with the Asiatic zone. Though having a very different fauna and flora, South America presumably forms part of the same geographical province so far as man is concerned, though there is evidence for thinking that he reached it very early. Until, however, more data are available for the pre-history of the American Indian, the great moulding forces, geographical or other, must be merely guessed at. Much turns on the period assigned to the first appearance of man in this region; for that he is indigenous is highly improbable, if only because no anthropoid apes are found here. The racial type, which, with the exception of the Eskimo, and possibly of the salmon-fishing tribes along the north-west coast, is one for the whole continent, has a rather distant resemblance to that of the Asiatic Mongols. Nor is there any difficulty in finding the immigrants a means of transit from northern Asia. Even if it be held that the land-bridge by way of what are now the Aleutian Islands was closed at too early a date for man to profit by it, there is always the passage over the ice by way of Behring Straits; which, if it bore the mammoth, as is proved by its remains in Alaska, could certainly bear man. Once man was across, what was the manner of his distribution? On this point geography can at present tell us little. M. Demolins, it is true, describes three routes, one along the Rockies, the next down the central zone of prairies, and the third and most easterly by way of the great lakes. But this is pure hypothesis. No facts are adduced. Indeed, evidence bearing on distribution is very hard to obtain in this area, since the physical type is so uniform throughout. The best available criterion is the somewhat poor one of the distribution of the very various languages. Some curious lines of migration are indicated by the occurrence of the same type of language in widely separated regions, the most striking example being the appearance of one linguistic stock, the so-called Athapascan, away up in the north-west by the Alaska boundary; at one or two points in south-western Oregon and north-western California, where an absolute medley of languages prevails; and again in the southern highlands along the line of Colorado and Utah to the other side of the Mexican frontier. Does it follow from this distribution that the Apaches, at the southern end of the range, have come down from Alaska, by way of the Rockies and the Pacific slope, to their present habitat? It might be so in this particular case; but there are also those who think that the signs in general point to a northward dispersal of tribes, who before had been driven south by a period of glaciation. Thus the first thing to be settled is the antiquity of the American type of man.