—For the purpose of my paper I accept the limitation suggested by Mr. Lockwood for retro-peritoneal neoplasms. The term implies a solid or cystic tumor growing behind the peritoneum, into its folds and not connected with any of the great retro-peritoneal organs. So we at once eliminate from our consideration tumors of the kidneys, pancreas, uterus and so-called broad ligament ovarian cysts. Neoplasms connected with any of the retro-peritoneal viscera usually present sufficient evidence in their history, symptoms and physical signs to enable us to ascribe their site of origin.
—Surgeons are not very careful in determining at the time of operation the true origin of the tumor with which they are dealing. The spirit of the pathologist is for the time eclipsed by the surgical emergencies. Therefore, I feel safe in assuming that many retro-peritoneal neoplasms have been encountered, the surgeon, recognizing the inoperable character of the