Of the various disorders of the heart, we must recognize palpitation, overaction, delirium cordis, peripheral hyperemia, variations in blood pressure, toxic angina and the manifestations of the rheumatic diathesis as due to auto-intoxication, for nearly all of these are features of experimental poisonings and all are relieved by measures helpful to the underlying alimentary cause. Lead syphilis, gout and other intoxications may be considered causes of angina, and cases of neuralgia of the cardiac plexus are often undoubtedly due to purins and other bases, but the autogenous origin of these conditions cannot be put upon a scientific basis until the circulatory organs of animals poisoned by metabolism end-products have been studied in a large number of cases. In experimental poisonings death is usually due to stoppage of the heart through the acute action of poisons of the major grade directly upon the cardiac plexus.