The development of the pilosebaceous apparatus at puberty and the commonly believed association of some cutaneous diseases, such as acne, with the "sex hormones" prompt the belief that the skin is intimately influenced by these agents. It has been shown that preparations of these hormones when applied to the skin may be absorbed and have systemic action.1 When androgens are injected intramuscularly, only a part of the total can be recovered in the urine.2 Since the skin is so permeable to the substances from without inward, it seemed possible that route of excretion might be through the sweat. An investigation therefore was made to determine to what extent androgenic substances occurred on the surface of the skin or in the sweat and oil. METHOD The subjects were encased in a rubber sack as far as the neck and placed in a heat cabinet. Some were given 50 mg.