But it is also possible that Mongols and Polynesians emigrated from the west and mixed with the former tribe. In any case the aborigines of America came over from the old world, and did not, as some suppose, in any way originate out of American apes. Catarhine or narrow-nosed apes never at any period existed in America.”[288] The same argument holds good if it be ascertained that both man and apes developed from a common ancestor. With these authoritative utterances from the most celebrated representatives of the development school, we shall rest the fanciful hypothesis of the autochthonic origin of the ancient American population. Some who may not concur in our opinion as to the question of man’s development from lower animal forms, may be willing to admit that the Americans had an old world origin, which certainly, in the light of facts, is the only rational view.[289] The unity of the human family is a theory, if not a fact, which is supported by a mass of testimony of the most diversified character. The habits and customs, the sympathies, the wants and fears, the simpler arts, as well as most bodily proportions, point to a relationship which finds its easiest explanation in a unity of origin. It is chiefly, however, in the ruder arts that this correspondence of style or type is observable. No better illustration of this offers itself than the similarity of form or forms in which flint arrow-heads are found in all parts of the world. It would be impossible for the most expert archæologists to assign a promiscuous collection of flint weapons to the various quarters of the globe from which they may have been gathered, simply on the ground of characteristic forms.[290] The common methods of producing fire by means of friction, employed with but slight variation among people the most remotely separated,[291] is an inexplicable fact, except on the ground of an early community of residence or identical inventive genius. The universality of certain architectural forms such as the pyramid, and the singular fact that they have generally been used for places of sepulture, offers an argument in the same direction. The fact indicates either an early community of residence or identity of mental organization. The physical resemblances of all races in certain stable features which have never been known to change, indicate a divergence from a common centre—from one type. The slight differences in the type of skull which characterize some nations from others, is no argument against original unity, since those peculiarities are certainly of more recent origin than the unknown events which at a remote period scattered men over the face of the earth.[292] Probably no difference between the races of men has been considered so essential as that of color, for none has furnished such reasonable ground for the views of polygenists as the marked contrast between the African and Caucasian types. Years ago the view that color was the result of