Why neoplasms of the spleen are so rare has never been satisfactorily explained, and doubtless never will be until we know the causes of tumors in general. We might speculate on the protected position of the organ, its freedom from irritation of any sort, such as comes to most other organs by the nature of both their position and work. The spleen escapes the unpleasant results of all but the most wide-spread calamities of the body, such as the septicemias and toxemias. The damage it sustains is commonly that carried to it by the blood-current.
Speculation even is not so easy when it comes to accounting for the raritv of its metastatic invasion in cases of the most extensive dissemination of tumor tissue. Its lymphatic supply is abundant enough, as is its blood-supply, to expose it to lodgment of circulating cells. If, however, we recognize the Hadley exposition of the