Rupture of the spleen may result from trauma or it may occur spontaneously. Spontaneous rupture is uncommon and usually occurs in the presence of splenomegaly, in most instances the result of malaria or typhoid. It has been reported less frequently during the course of puerperal sepsis, relapsing fever, pneumonia, cirrhosis of the liver, leukemia, typhus and infectious mononucleosis. Several cases have been reported in which it occurred during a normal pregnancy. In a few instances rupture had occurred spontaneously in a healthy individual with a normal spleen. Attempts to explain this phenomenon are confusing and, from a practical point of view, purely academic. Hamilton Bailey dismissed the subject by stating that "only the spleen can behave in this curious manner," a remark reminiscent of Galen, who spoke of the spleen as an organ "full of mystery." The following report illustrates most of the diagnostic problems involved and bears out another