• Two patients exhibited profuse sweating limited to the temporal region on one side. The sweating accompanied salivation during the mastication of food and necessitated wiping the area repeatedly at every meal. In both patients there was a history of parotitis following abdominal surgery. Tests with acetylcholine, pilocarpine, and histamine in one patient led to the conclusion that, in the process of recovery from parotitis, regenerating parasympathetic salivary fibers must have been misdirected into the sweat glands, which normally have a sympathetic innervation, and that these responded thereafter in a manner to be expected from their abnormal, dual nerve supply. Both patients were relieved permanently of this annoying syndrome by intracranial division of the glossopharyngeal nerve.