In dogs with gastric fistulas (vagally innervated) and in dogs with pouches of the entire stomach (vagally denervated), the secretion of acid in response to Urecholine or histamine is depressed for at least 3 hrs. following intraven. admn. of 4 mg./kg. of hexamethonium bis-trimethylammonium chloride. The inhibition is greater in the vagally innervated than in the vagally denervated stomach prepns.