Of the 654 cases of lithiasis of renal origin operated on at the Mayo Clinic up to June 1, 1915, 363 stones were removed from the kidney and 230 were found lodged in some portion of the ureter. To this number should be added sixty-four cases in which a stone lodged in the ureter was either removed at the time of the cystoscopic manipulation or was passed immediately after, making a total of 294 cases of stone in the ureter for consideration. It is our purpose to review a few of the various clinical data involving their diagnosis. Localization of Pain. —Pain as a result of stone in the ureter occurs from two conditions: namely, (1) because of intrarenal tension as a result of urinary obstruction, and (2) because of localized infectious changes. A review of the localization of pain in our series of cases is of interest. Pain was