The term "chronic ulcerative colitis" has come to mean a definite disease entity, which presents characteristic clinical, pahologic, proctoscopic and roentgenologic data. Clinically, the disease is characterized by frequent rectal discharges of mucus, blood and pus; the presence of diarrhea depends on the extent of involvement of the colon and the severity of the disease. Usually the infection begins in the rectum and spreads upward, and frequently affects the entire colon. If, therefore, the lesions involve only the rectum and rectosigmoid, the stools may be scybalous and the patient may complain of constipation, while having twelve or more bloody, purulent rectal emissions daily. The result of the long-continued passage of blood and the toxemia from the severely infected colon is general wasting, anemia, emaciation and, eventually, chronic invalidism. Obviously the symptoms of this disease may be readily confused with other conditions in which mucus, blood and sometimes pus are discharged