The following two cases of complete heart-block are considered worthy of report because of several unusual features shown by electrocardiograms. REPORT OF CASES Case 1. —Mrs. E. P., an American housewife, aged 39, had been under observation in the Washington University Dispensary for two years. She first came to the dispensary because of various gynecologic complaints associated with retroversion of the uterus. At that time it was found that she had an unusually slow pulse rate, and electrocardiograms revealed the presence of complete heart-block. This condition had been constantly present since, but in spite of this fact she had had no cardiac symptoms aside from slight dyspnea on exertion. She had never had a syncopal attack. Physical examination of her heart had constantly shown moderate enlargement of the cardiac dulness, the presence of an apical systolic murmur transmitted to the axilla, and a faint aortic systolic murmur poorly transmitted. The