THE SPLEEN deserves the serious consideration of the surgeon because of its peculiar properties. Anatomically the spleen is well protected by its bony housing, yet it is extremely vulnerable if this shelter is penetrated. The normal spleen is quite friable and covered by a delicate capsule. Enormous quantities of blood traverse this organ, but, once injured, it has poor healing properties. It has been estimated that one-sixth of the total volume of blood in the body can be stored in the spleen.1 Normally, then, the size of the spleen varies greatly. Its reticuloendothelial tissue filters great numbers of bacteria out of the blood. The spleen contains end-arteries which subject this viscus, like the kidney and heart, to infarction. I have the opportunity of seeing many young men who are exposed to abdominal trauma, and I have become interested in this problem. Trauma to the spleen from an external source