════════╤════════╤═════════════════╤═════════════════ │ NO. OF │ │ HEMOLYTIC │CULTURES│ PNEUMOCOCCI │ STREPTOCOCCI ────────┼────────┼────────┬────────┼────────┬──────── │ │ NO. │PER CENT│ NO. │PER CENT │ │POSITIVE│POSITIVE│POSITIVE│POSITIVE ────────┼────────┼────────┼────────┼────────┼──────── Bronchus│ 44│ 56.9│ 14│ 31.8│ 22 Lung │ 53│ 77.3│ 13│ 24.5│ 8 Blood │ 87│ 65.5│ 11│ 12.6│ ────────┴────────┴────────┴────────┴────────┴──────── ════════╤═════════════════╤═════════════════ │ │ │ STAPHYLOCOCCI │ B. INFLUENZÆ ────────┼────────┬────────┼────────┬──────── │ NO. │PER CENT│ NO. │PER CENT │POSITIVE│POSITIVE│POSITIVE│POSITIVE ────────┼────────┼────────┼────────┼──────── Bronchus│ 37│ 84.1│ 96│ 79.3 Lung │ 26│ 49.1│ 70│ 45.7 Blood │ │ │ 1│ 0.5 ────────┴────────┴────────┴────────┴──────── Pneumococci, the recognized cause of lobar pneumonia, were found in the lungs in 73.3 per cent of autopsies; failure to find the microorganism in all instances is doubtless the result of its disappearance from the lung, which, it is well known, occurs not infrequently particularly during the later stages of the disease. In 65.5 per cent of instances of fatal lobar pneumonia pneumococci have entered the heart’s blood. Hemolytic streptococci unlike pneumococci were found more frequently in the bronchi than in the lungs; this microorganism which exhibits little tendency to disappear, once it has established itself within the body, found entrance into the bronchi in 31.8 per cent of instances of lobar pneumonia and in 24.5 per cent entered the lungs. Its invasive power is further illustrated by its penetration into the heart’s blood approximately in half this proportion of autopsies. Staphylococci enter the bronchi in many instances (50 per cent), but relatively seldom (15.1 per cent) invade the lung and rarely if ever penetrate into the blood. The high incidence, namely, 84.1 per cent, of B. influenzæ in the bronchi is particularly noteworthy; it exceeds that of pneumococci, the well-recognized cause of lobar pneumonia, within the lung. It is found much less frequently within consolidated lung tissue and shows no tendency to invade the heart’s blood. B. influenzæ finds the most favorable conditions for its multiplication within the bronchi. In view of the frequent occurrence of coexisting lobar and bronchopneumonia it has appeared desirable to determine how far the existence of obvious bronchopneumonia modifies the bacteriology of lobar pneumonia. In Table XXXI the incidence of pneumococci, hemolytic streptococci, staphylococci and B. influenzæ after death with lobar pneumonia on the one hand is compared with their incidence after combined lobar and bronchopneumonia on the other.