With a fluorescence method for the localization of histamine, fluorescence was found in cells, located in the base of the gastric glands, and in the few submucosal mast cells. The histamine-containing cells of the glands did not stain like the parietal, chief or mast cells. By determinations on serial sections of the mucosa the distribution of histamine could be compared with the histamine forming capacity. Both resided in the same part of the gastric glands. The distribution of the parietal cells did not indicate any connection with histamine and its formation.