The intoxication which is developed when splenectomized mice are fed with fresh spleen is more regular in occurrence when the feeding experiment is carried out four or five days after splenectomy than when it is done at later periods. The intoxication is easily recognizable even in its less severe forms by a lengthening of the coagulation time of the blood.
An intoxication of the same character is produced when splenectomized mice are fed with the mucous membrane of the stomach and upper small intestine. Bone marrow and dried blood probably give the same reaction in a somewhat milder form. The other organs either give no intoxication at all when fed, or in certain instances the thyroid, adrenal, and salivary gland (mouse) give intoxications of a different character which affect intact mice and splenectomized animals equally.
The spleen or the gastro-intestinal mucosa is equally effective in producing the intoxication, whether it be derived from heterologous or homologous species.
Certain experiments, not reported in detail, indicate that the susceptibility to the intoxication disappears in time and that this time may be shortened by repeated feedings with sublethal amounts of organ substance.