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OCR Rendition - approximate
iv THE RIDGES AND THEIR USES 57 thumb and fingers cut the ridges at small angles, say, very roughly, of 15 degrees. The supposition is therefore untenable . that the courses of the ridges are wholly determined by the flexures. It appears, however, that the courses of the ridges and those of the lines of flexure may be in part, but in part only, due to the action of the same causes. The fact of the creases of the hand being strongly marked in the newly-born child, has been considered by some to testify to the archaic and therefore important character of their origin. The crumpled condition of the hand of the infant, during some months before its birth, seems to me, however, quite sufficient to account for the creases. I possess a few specimens of hand prints of persons taken when children, and again, after an interval of several years : they show a general accordance in respect to the creases, but not sufficiently close for identification. The ridges on the feet and toes are less complex than those on the hands and digits, and are less serviceable for present purposes, though equally interesting to physiologists. Having given but little attention to them myself, they will not be again referred to. The ridges are studded with minute pores which are the open mouths of the ducts of the somewhat deeply-seated glands, whose office is to secrete perspiration : Plate 10, n, is a good example of
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