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22 retained at birth, as shown by the remarkably tight and persistent grasp of a newly-born baby—a fact which is well known to accoucheurs.

The theory of the descent of man from the lower animals is also strongly supported by the presence in the human body of a number of vestigial organs, which are now useless in the human economy, but whose homologues in other animals have well-defined functions. Among such organs are the coccyx, intra- and supra-condyloid foramina of the humerus, and the appendix vermiformis. But indeed the detailed structure of the entire human body is utterly inexplicable on any other hypothesis. See Dr. Arthur Keith's volume on The Human Body in this Library.

But of all the problems relating to the origin and descent of Man the most important is to account for the great superiority of his reasoning powers. The hypothesis, that this profound distinction is primarily due to his being in possession of true hands, is the most feasible explanation that has hitherto been advanced on the subject. By means of hands man manufactured tools and weapons, and utilized them to such an extent that they ultimately superseded his natural means of defence. The knowledge, skill and experience thus acquired gradually led to an increase in brain substance—the undoubted organ of thought. This handicraft skill was absolutely a new departure in the history of organic evolution, as no other animal is, or ever was,