The problem of common duct stones has been discussed frequently in the past decade. That continued emphasis and discussion are advisable is suggested by the history of previous operation on the biliary tract in 27% of our patients who had choledocholithiasis. Other authors have noted a similar incidence of previous, unsuccessful operations in patients with common duct stones.1 A group of 175 consecutive cases in which common duct stones were removed at operation by one of us (J. M. W.) during the period from 1940 to July, 1950, have been reviewed. The only cases discarded from the series were those in which choledocholithiasis was associated with tumors and strictures of the common duct or acute pancreatitis and the latter conditions were the primary consideration, clinically and at operation. Although such a study does not provide data on the incidence of choledocholithiasis in patients undergoing cholecystectomy, the incidence has ranged from 10 to 16% at the Mayo Clinic in the past few years.2 SYMPTOMATOLOGY The sex ratio was somewhat unusual, with 108 women and 67 men, a ratio of only 1.6 to 1.0. The ages of the patients ranged from 25 to 80 years and averaged 55.6 years.Pain.-Typical biliary colic, severe enough to necessi¬ tate the administration of hypodermic injections for relief, was present in 125 patients (71.4%). Pain that was atypical in location but severe enough to require hypo¬ dermic medication (6 patients) and typical colicky pains of only moderate severity (7 patients) might well be in¬ cluded in the so-called typical biliary colic group because of the recognized variability of biliary tract pain (total incidence, 79% ). In the 37 patients remaining, the pain was classified as atypical in location and occurrence in 21, and was essentially absent in 16 patients (9% ).A history of very frequent episodes of colic was a notable feature in very few patients of this series. Certain authors have stressed the importance of episodes occur¬ ring at intervals of 14 days or less as evidence of the presence of stones in the common duct.3Jaundice.-A clinical diagnosis of jaundice was made on admission in 86 cases, and in 36 of this group there was also a history of previous episodes of jaundice. A previous history of jaundice was noted for an additional 28 patients. A total of 114 patients, or 65% of the entire series, thus gave a history or clinical evidence of jaundice. Thirty-five per cent had never been aware of any jaundice.The inadequacy of jaundice alone as an indication of the presence of common duct stones in cholelithiasis patients has been noted by many authors. The incidence of jaundice with choledocholithiasis has varied from 53 to 76% in previous studies.4 Jaundice has greater sig¬ nificance when accompanied by severe pain and inter¬ mittent acholic stools 5 than when not so accompanied, and Buxton and Burk have stressed the importance of recent and frequent episodes of jaundice.48 Conversely, the absence of jaundice is no guarantee of the absence of common duct stones. Thirty-five per cent ...