If 0.1 to 0.2 cc. of nicotine sulfate or nicotine picrate diluted with physiologic solution of sodium chloride to a concentration of 1: 100,000 is injected intradermally into a human being, during or immediately after the injection "goose flesh" appears in an irregularly shaped area, 3 to 5 cm. in diameter, surrounding the puncture and subsides within two minutes. The susceptibility to the pilomotor effect of nicotine seems to parallel the tendency of "goose flesh" to develop physiologically in the subject. The reaction fails to appear if the postganglionic sympathetic fibers of the tested area of skin have degenerated. Furthermore, it fails to appear in certain cutaneous lesions, for instance, in urticarial wheals. Local anesthetics destroy the response even in high dilutions. The test is based on the action of nicotine on sympathetic nerve receptors in the skin. From there the impulse reaches the pilomotor endings by way of an axon reflex. Experiments on the nature of this mechanism will be published in theProceedings of the Society for Experimental Biology and Medicine, theJournal of Pharmacology and Experimental Therapeuticsand theJournal of Investigative Dermatology.