SummaryPancreatitis complicating mumps produces a characteristic symptom complex. It occurs in both sexes and at any age. In out series the extremes of age were six years and thirty years. The onset is sudden between the fifth and the eleventh days of the illness with nausea, anorexia and fever. The temperature rises in a day or two to 103° or 104° F. in the moderately severe cases, and returns to normal in three to fice days. The pulse is usually slow in relation to the temperature. The patients complain of malaise, nausea, headache and abdominal pain and usually vomit. The pain and tenderness in our patients were constipated, and diarrhea which has been reported by other observers did not occur in our series. There was no glycosuria. Information from autopsy examinations is limited to 2 cases. The pathologic changes in the pancreas reported by Lemonie and Lapasset are comparable to the changes found by Wollstein in the parotid glands of monkeys experimentally inoculated with mumps. The abnormal findings in the pancreas described by the French authors are in all probability only a little more advanced than those which occur in the patients who recover.