=Autopsy 473.=—A. D. P., white, aged twenty-one, a student from Missouri, had been in military service two weeks. He was admitted to the hospital with influenza twenty-eight days before his death, and four days after admission there were signs of pneumonia. Paracentesis was performed on the right side on the eleventh day after admission; 4 c.c. of cloudy fluid which contained Pneumococcus III were obtained at this time and later in the day 800 c.c. were withdrawn. On the thirteenth day attempted withdrawal of fluid from both pleural cavities failed. On the eighteenth day aspiration of the right pleural cavity yielded only 30 c.c. of fluid. On the nineteenth day 400 c.c. of purulent fluid were withdrawn from the right pleural cavity. On the twenty-fifth day there was cyanosis and delirium. Shortly before death aspiration of the right pleural cavity was attempted, but only 4 c.c. of fluid were obtained. =Anatomic Diagnosis.=—Chronic bronchopneumonia with lobular and peribronchiolar consolidation in left lung; fibrinopurulent pleurisy on both sides; purulent bronchitis and bronchiectasis. On removal of the sternum, encysted purulent pleurisy is found between the inner surface of the right lung and the pericardium; there is here 450 c.c. of very thick creamy, greenish yellow pus entirely separated from the remainder of pleural cavity. The external part of the cavity contains 1,450 c.c. of fluid and voluminous masses of firm fibrin which placed in a measuring cylinder occupy 450 c.c. The left pleural cavity contains 400 c.c. of seropurulent fluid in which there is abundant sediment of fibrinous particles. The right lung is compressed; the bronchi exude purulent fluid. The left lung is voluminous; in the upper and lower lobes there are small yellowish gray nodules of consolidation, grouped in clusters, and gray patches of lobular consolidation occur. Bronchi are dilated and filled with purulent fluid. Bacteriologic examination shows the presence of Pneumococcus III obtained in pure culture from the blood of the heart and from the right pleural cavity. S. viridans is grown from the left lung; a plate from the right bronchus contained B. influenzæ, S. viridans and a few colonies of staphylococcus and M. catarrhalis.