The conclusions resulting from this study of the relation of focal infections to functional psychoses may be summarized as follows:1. The removal of infected teeth and tonsils from 27 cases showing manic-depressive, dementia præcox, and psychoneurotic reactions has been followed by no more mental benefit than was shown by a comparable group of 33 patients from whom such supposed foci of infection were not removed. There were no recoveries or distinct improvements other than those prognosticated irrespective of focal infection.2. The Rehfuss method of fractional gastric analysis is not to be relied upon as a means for determining gastric infection. The bacteria found in the stomach contents by this method may be derived for the greatest part or entirely from the swallowed saliva. These studies are being continued, not only for the purpose of obtaining further facts regarding focal infection in the psychoses, but as a part of a general plan to afford psychotic patients all available opportunities for benefit.