connection with one another, producing thus a transverse arrangement, and in D 1, 2 and 5 a more oblique one. In the palm this correspondence of ridges with flexion lines of joints is not found so much except in the central part of this surface. But the oblique and longitudinal ridges of the palm where it becomes concave in the action of folding the hand over a globular object are well shown there also to correspond with such action. This general grouping of ridges is seen, _mutatis mutandis_, to belong to all the palms and soles of lower Primates, and the illustrations given will speak for themselves, so that little need be said on each. Reasons for Arrangement Observed. When one discusses the forces in action on man’s hand which are claimed to have thus arranged the ridges, in regard to the question of use and habit, little more need be added as to those of other Primates, and it is because we know more about ourselves than them, and our own palms and soles are available for inspection, that I have taken man as the example. The main question is the old and now familiar one: “Are these ridges arranged as we see them _by_ use and habit, or adapted _for_ use?” Dr. Hepburn and the orthodox Selectionist would say that, of course, their mode of arrangement is an adaptation governed by selection for preventing slipping in the action of grasping an object by the hand, and in the foot for preventing slipping in walking. This does not take into account the question as to how the original slight shifting of the ridges in the earliest man and in lower forms could have had selective or survival value, for example, the insignificant sparse groups of ridges on the palm, sole and _tips_ of the digits in a hedgehog or squirrel. As things are now they _do_ subserve these purposes. But I think this matter of prevention of slipping has been much exaggerated, though I may be told that this is a matter of opinion and not a valid argument against the hypothesis. Foot of Man. [Illustration: Fig. 60 S. K. Right foot drawing of papillary ridges made from impression.]