THE ulcerating lesions within the grasp of the pyloric ring is difficult. Such ulcers are relatively rare in individual practice, and in the literature there are only a few widely scattered studies of their significance. The available articles were reviewed as a background for the present analysis of 20 cases of lesion of the pyloric ring for which satisfactory follow-up records were at hand. SUMMARY OF THE LITERATURE Butsch,1in 1935, summarized the experience at the Mayo Clinic with pyloric lesions. He found reports of 46 cases of pyloric ulcer in the surgical records there. Only 4 lesions had been accurately localized within the ring by roentgenologic studies. Ten lesions had been excised, and each had been found to be benign. In discussing this paper, Eusterman2said (1) that peptic ulcers of the ring are difficult to diagnose in spite of the fact that patients with such lesions