═══════════╤══════════════╤══════════════╤══════════════╤══════════════ AUTOPSY │ DURATION OF │ BLOOD │ LUNGS │ BRONCHUS │ ILLNESS │ │ │ ───────────┼──────────────┼──────────────┼──────────────┼────────────── 420 │11 days │S. hem. │S. hem., B. │ │ │ │ inf., S. │ │ │ │ aur. │ 402 │14 days │Pneum. IV, │ │ │ │ S.hem. │ │ 370 │17 days │ │S. aur. │S. aur., │ │ │ │ Pneum. IV, │ │ │ │ B. inf. 457 │17+ days │ │ │Pneum. IV, B. │ │ │ │ inf. 421 │19 days │S. hem. │Pneum. IV, S. │ │ │ │ hem. │ 445 │27 days │S. hem. │Pneum. IV, S. │S. aur. │ │ │ aur. │ 473 │28+ days │Pneum. III │S. vir. │B. inf., S. │ │ │ │ vir., │ │ │ │ staph., M. │ │ │ │ catarr. 499 │36 days │S. hem. │ │S. hem. B. │ │ │ │ inf. ───────────┴──────────────┴──────────────┴──────────────┴────────────── Thrombosis of lymphatics in the wall of bronchi adjacent to blood vessels and in interlobular septa occurs, and occasionally organization of the fibrinous plug within the lymphatic is in progress (Autopsies 283, 425 and 463). Fibroblasts and capillaries penetrate from the wall of the lymphatic into a mass of hyaline fibrin which fills the lumen. =Unresolved Bronchopneumonia.=—The most common type of pneumonic lesion following influenza is characterized by acute inflammation of the alveoli immediately adjacent to the bronchioles and the lesion is associated in many instances with hemorrhage or edema. If this lesion persists unresolved during several weeks, evidences of chronic inflammation are found. Peribronchial, perivascular and interlobular connective tissue is thickened and richly infiltrated with lymphoid and plasma cells, large mononuclear cells and many young fibroblasts. Interalveolar septa adjacent to the walls of bronchi and between alveoli surrounding inflamed bronchioles are implicated in the process. Interstitial changes characterize the lesion only in its late stage. It appears undesirable to give the name “interstitial pneumonia” to the early stage of a lesion which begins and in most instances terminates as an acute relatively superficial inflammation of the bronchi, bronchioles and peribronchiolar alveoli.