A. Necrosis and suppuration with formation of one or several abscesses usually below the pleura and almost invariably caused by hemolytic streptococci. B. Interstitial suppurative pneumonia caused by hemolytic streptococcus. C. Multiple abscesses in clusters caused by staphylococci. Suppurative pneumonia with necrosis and abscess formation will be discussed in this section. Pulmonary abscesses which occurred in 43 autopsies may be included in this group; in 4 of these autopsies abscess and interstitial suppurative pneumonia occurred in the same individual. These abscesses were much more frequently situated in the lower than in the upper lobes and more often in the right than in the left lung. In most instances there was one or several abscesses situated below the pleura of one lobe; occasionally abscesses occurred in two lobes of the same lung or in both lungs. The distribution was as follows: Abscess in only one lung occurred in right upper lobe in 6 autopsies; middle lobe, 3; lower lobe, 15; left upper lobe, 2; lower lobe, 16. Abscesses occurred in both right and left lower lobes, twice. The usual situation was at the lower and posterior part of the lower lobe at or near the basal edge, less frequently below the posterior border or upon the basal surface of the lobe. These abscesses in almost every instance were found immediately below the pleural surface, so that they appeared upon the pleura as opaque yellow spots usually surrounded by narrow zones of hemorrhage. In one instance (Autopsy 376) the abscess cavity was separated from the pleural cavity by remains of the pleura which was as thin as tissue paper and in other instances perforation had occurred (Fig. 9). In Autopsy 480 the abscess cavity which had perforated the pleura was in free communication with a bronchus of medium size. In most instances of suppurative pneumonia there have been associated lesions of bronchopneumonia which have been peribronchiolar, hemorrhagic or lobular and have exhibited no unusual characters. The abscess or abscesses are situated within an area of pneumonic consolidation which is not limited by lobule boundaries and has not the characters of bronchopneumonic consolidation. In some instances this consolidation is limited to a zone immediately about the abscess, but often it involves the greater part of a lobe. The tissue is laxly consolidated and flabby; on section it has a dull, conspicuously cloudy appearance and is grayish red, pinkish gray or gray; it is homogeneous or very finely granular. Turbid gray fluid, which sometimes resembles thin pus, oozes from the cut surface.