to the pleural exudate, a fibrino-purulent pleurisy or empyema. As we have subsequently learned the pleurisies developing late in the course of the influenza and those which persist after the pulmonary inflammation has passed are prone to be of a purulent kind. There have been a fair number of cases of empyema brought to our attention by the surgical department in the bacteriological laboratory of the hospital, subsequent to the wave of epidemic influenza. If one were to base his finding alone upon observations obtained in the operating room, he would be impressed by the fact that the pleurisy accompanying the epidemic of influenza is of a purulent type. On the other hand, if one were alone to consider the findings at the autopsy table during the five weeks of the epidemic, one would be of the opinion that the pleurisy is of very minor consequence and of a serous type. It is this changing picture which is particularly to be kept in mind. And our experience indicates that during the height of the influenzal lesions of the lung when the pulmonary lesions develop so rapidly that we obtain a pleural reaction closely resembling the inflammatory conditions in the lung and also containing bacteria not unlike the pulmonary flora. Dr. Holman has obtained the influenza bacillus and other varieties from the pleura during these early periods of the pulmonary inflammation. It is more than probable that just as in the infection of the lung tissue where there is a change in the type of the bacteria present, so, too, the flora of the pleura alters in the succeeding stages of the pulmonary reaction. In the late event of empyema we have not observed the influenza bacillus. The majority of the empyemas possess hemolytic streptococci and occasionally pneumococci. _Heart_ During the acute epidemic and while the disease was at its height it was remarkable how few cases showed involvement of the heart. It was the common observation that even during intense illness the heart action remained fairly stable and did not indicate an effect by intoxication as might be expected from the severity of the illness. In as much as the majority of deaths occurred within relatively few days of the onset of the severe infection, the type of lesion that would be looked for in the heart would be either bacterial inflammatory products within the pericardium, myocardium or endocardium or toxic lesions of musculature alone.