Acute intestinal intoxication in infants has been generally regarded as due to an infection. The lack of any unanimity of opinion among workers in this field as to the responsible organism, lead us to consider the possibility of the toxemia being due to a chemical toxin, in the production of which various types of organisms might play a more or less important part. Schloss1 recently reported the finding of a substance of unknown nature in the blood of cases of intestinal intoxication which proved to be toxic to guinea-pigs. Starling,2 in 1902, and later Popielski,3 reported the finding of a toxic substance in extracts of normal intestinal mucous membrane. This toxin, when injected into animals, caused a symptom complex consisting of increased peristalsis, periods of depression and narcosis, vasodilation, and fall of blood pressure. Barger and Dale4 regarded this substance as identical with the amine base β imino-azolylethylamine (histamine) which