Two points are certain: first that the main differences between the branches of our race were fixed in the earliest epoch of our terrestrial life; secondly, that in order to imagine a period when these physiological cleavages could have been brought about, we must go back to the time when the influence of natural causes was far more active than it is now, under the normal and healthy conditions. Such a time could be none other than that immediately after the creation, when the earth was still shaken by its recent catastrophes and without any defence against the fearful effects of their last death-throes. Assuming the unitarian theory, we cannot give any later date for the separation of types. No argument can be based on the accidental deviations from the normal which are sometimes found in certain individual instances, and which, if transmitted, would certainly give rise to important varieties. Without including such deformities as a hump-back, some curious facts have been collected which seem, at first sight, to be of value in explaining the diversity of races. To cite only one instance, Prichard[88] quotes Baker’s account of a man whose whole body, with the exception of his face, was covered with a sort of dark shell, resembling a large collection of warts, very hard and callous, and insensible to pain; when cut, it did not bleed. At different periods this curious covering, after reaching a thickness of three-quarters of an inch, would become detached, and fall off; it was then replaced by another, similar in all respects. Four sons were born to him, all resembling their father. One survived; but Baker, who saw him in infancy, does not say whether he reached manhood. He merely infers that since the father has produced such offspring, “a race of people may be propagated by this man, having such rugged coats and coverings as himself; and if this should ever happen, and the accidental original be forgotten, it is not improbable they might be deemed a different species of mankind.” Such a conclusion is possible. Individuals, however, who are so different as these from the species in general, do not transmit their characteristics. Their posterity either returns to the regular path or is soon extinguished. All things that deviate from the natural and normal order of the world can only borrow life for a time; they are not fitted to keep it. Otherwise, a succession of strange accidents would, long before this, have set mankind on a road far removed from the physiological conditions which have obtained, without change, throughout the ages. We must conclude that impermanence is one of the essential and basic features of these anomalies. We could not include in such a category the woolly hair and black skin of the negro, or the yellow colour, wide face, and slanting eyes of the Chinaman. These are all permanent characteristics; they are in no way abnormal, and so cannot come from an accidental deviation.