In a previous paper1 the mechanism of the gastric phase of secretion was discussed. Following the ingestion of certain food substances, such as meat, a humoral stimulant of gastric secretion appears in the blood stream. This stimulant is either a product of food digestion and is absorbed through the antrum or a hormone prepared by the antral cells and then liberated into the blood. At any rate it is the antrum, approximately the distal fifth of the stomach, which is involved in this mechanism. The humoral stimulant is then carried to the glands of the fundus, and there produces secretion. Neither the vagus nor the splanchnic nerves are necessary for this mechanism, for in a transplanted pouch made from the fundus of the stomach, the secretion still takes place.2 In such a transplanted pouch there are two possible sites on which the stimulant may act: (1) the intrinsic