The experimental finding that secretion of hydrochloric acid increases during sustained anxiety is not consistent with Cannon's theory of sympathetic excitation and parasympathetic inhibition in emergencies. The unqualified extension of this theory from acute emergency reactions to chronic anxiety appears to be invalid. Utilizing a group of chronically anxious subjects and a 'normal' control group, it was found that the gastric acidity of the former was greater, but a clear distinction between the responses to acute and sustained anxiety could not be determined, because considerable sustained anxiety occurred in the control group in anticipation of the experimental procedure. The nature of gastric secretion in acute anxiety was not clarified.