quinidin is more likely to cause resumption of normal rhythm in those cases in which the fibrillation is of recent onset.2. The rheumatic cases, though not more likely to return to sinus rhythm, did show a greater tendency to maintain the restored rhythm, and to be benefited, clinically, by the change.3. The most striking feature in the successful use of quinidin is the subjective relief experienced by the patient; many of these patients immediately expressed their pleasure in no longer feeling the annoyance caused by the irregularity. We believe that this subjective relief offers the most certain indication for the use of quin¬ idin, and that those patients, in particular, who are troubled by the irregularity should be given the benefit of quinidin therapy. 4. Though our series is small, we are of the opinion that the restoration of the normal rhythm is often of real value to the patient as an aid to the maintenance of compensation. Under proper conditions, quinidin offers enough hope of relief to warrant its continued use, though the treatment of auricular fibrillation had better not be undertaken outside a hospital until the routine of safe treatment is more carefully worked out. 5. We do not believe that patients with fibrillation of long duration must be denied the possible benefits of quinidin therapy, simply because the condition has existed for a long time.