The influence of the vagus nerve on the gastric motor mechanism has inspired extensive investigation; nevertheless, diversity of opinion concerning its precise effect on the human stomach still exists. As a result, vague and paradoxical functions have been suggested. Apparent discrepancies are due in part to the infrequency of direct observations on man. These, however, are being gradually eliminated through the recent controlled investigations of human gastric function. The wider recognition of indications for indirect or physiologic surgical treatment has increased the number of opportunities for the study of the neurogenic control of human function. During recent years attempts have been made to ameliorate certain abnormal states by the extirpation of organs related physiologically to the nature of the fundamental disease. Although these surgical procedures have been instituted primarily for their therapeutic effect, nevertheless, they have provided opportunities for the investigation of the physiologic properties of these organs. Thus, bilateral