III. GENERAL CHARACTERISTICS OF HUMAN HAIR Man is unique among the mammals in his complete lack of tactile hairs. So far as is known, every other mammal possesses them. They are the first to appear in the embryo and persist after all others have been lost through disease or phylogenetic reduction. But with man they are found, if at all, only as transient embryonic rudiments. This absence of true tactile hairs may be mentioned as one of the few qualitative differences between man and all other mammals. In most respects, human hair conforms fairly well in character and distribution to the hair of other members of the class, especially the anthropoid apes. HAIRLESS REGIONS OF THE BODY The human species is by no means the most nearly hairless animal, for, as already mentioned, most cetaceans and many representatives of other orders are less well provided. But in man, the great