Since 1921, we have studied 130 patients with exophthalmic goiter (Graves' syndrome).1Of these, seventeen, or 12 per cent., died, as shown in the accompanying table. Our purpose in this article is to analyze these fatalities, to emphasize the frequent occurrence of the "acute crises," and to describe our experiences with thyroxin administered intravenously in the treatment of these "acute crises." ANALYSIS OF DEATHS Three patients died of complications unrelated to the original disease. Of these, two died of carcinoma of the stomach, and one of lymphatic leukemia. In the last patient, the symptoms referable to exophthalmic goiter were in abeyance at the height of the leukemia, though leukemia is itself associated with ah elevation of the basal metabolism. One patient died of cardiac insufficiency, undoubtedly due to exophthalmic goiter. This woman was moribund when admitted to the hospital, and died thirty-six hours after admission. One woman died of