At present we are neither doubting the reality nor measuring the amount of this paradox; we are only asking in which of two ways it has been interpreted. What has been the effect of the antagonism between the philologico-grammatical and the philologico-glossarial test? Which has told most? the difference or the likeness? Has the first determined investigators to separate what the latter unites, or has the latter united what the former separates? The answer to this is--that the likeness in the grammars has been generally considered to over-ride the difference in the vocabularies; so that the American languages are considered to supply an argument in favour of the unity of the American population stronger than the one which they suggest against it. The evidence of language, then, is in favour of the unity of all the American populations--the Eskimo _not_ excepted. The evidence, however, of language, forms but a fraction of the argument; indeed, it is only one part of the great division which contains the _moral_ elements of ethnological difference or likeness in opposition to the _physical_. The complementary question as to the unity or non-unity of the general social or mental development of the aboriginal American still stands over. What are the facts which chiefly influence opinion here? In which direction is their influence? The facts are of two kinds-- 1. Those which disconnect the Eskimo-- 2. Those which disconnect the Mexicans and Peruvians from the other Americans--the former on the strength of an inferior, the latter on the score of a superior civilizational development. What is their value? This will be best ascertained when _all_ the sections of the American population involved in the question have been noticed. At present the Eskimo only have been dealt with; the Mexicans and Peruvians still remaining to be described. Enough, however, has been said to show that the question has taken a complication; since the evidence of the _non_-philological moral and mental phænomena is _against_ the unity of the American population--the Mexicans and Peruvians on one side, and the Eskimo on the other being isolated. The evidence, however, of the moral and mental phænomena (philological and _non_-philological combined), is but one division of the argument. The complementary question as to the unity or non-unity of the physical conformation of the aboriginal American still stands over. What are the facts which chiefly influence opinion here? _Mutatis mutandis_, the statements which have just been made may _very nearly_ be made here. The test of physical conformation is considered to exclude the Eskimo; and the test of physical conformation is considered to exclude, if not the Mexican, at least the Peruvian. * * * * *