The physical examination showed a well developed and well nourished male, who was slightly jaundiced and markedly prostrated. The conjunctivæ were injected. The heart, abdomen, extremities, and right lung were negative. In a small area outside the left nipple and extending into the axilla, tubular breathing and subcrepitant râles were heard, but no definite signs of consolidation were made out. The physical signs remained the same during the eight-day stay in the hospital. At entrance his temperature was 102.8°F. In twelve hours it fell to 100°F., then rose to 103°F., where it stayed for twenty-four hours, falling by lysis and remaining normal for the three last days. On his eighth day in the hospital, the patient suddenly collapsed and died within fifteen minutes. The autopsy was held one hour after death and the essential findings were as follows:— The peritoneal cavity contained 100 cubic centimeters of clear, straw-colored fluid and the viscera, particularly the liver, were acutely congested. The right side of the heart was greatly dilated; and on opening the pulmonary artery _in situ_ considerable blood gushed forth under pressure and a huge, tortuous embolus completely filled the vessel and its branches (Fig. LIII). The veins of the vesicoprostatic plexus on the right, and the right internal and external iliac veins contained thrombi, and it was evidently from this region that the embolus had been set free. The pleura of the lower third of the left lung over an oval area about 13 × 5 centimeters was bound to the parietal pleura by pinkish-grey, translucent adhesions which were evidently of comparatively recent origin. Here the lung was firmly consolidated, but it was apparently normal elsewhere. On section the consolidated area was silvery grey, with a pink tinge, comparatively dry and smooth. In some areas, especially about the bronchi, delicate, silvery grey, translucent strands could be seen sweeping out into the surrounding lung, which contained no air. The remainder of the lung was air-containing. The trachea showed moderate congestion most marked near the bifurcation. The hilic lymph nodes were enlarged, soft, congested, and succulent, as well as anthracotic. [Illustration: FIG. XXIX. THE VESSELS OF THE ALVEOLAR WALLS ARE CONGESTED AND CONTAIN A LARGE NUMBER OF LEUCOCYTES. THE EXUDATE IS COMPOSED ALMOST ENTIRELY OF WHITE BLOOD CELLS, IN THE BODIES OF WHICH INNUMERABLE BACTERIA MAY BE SEEN. COMPARE FIGURES XXI, AND XXXII. ]