════════════════════════════════════════════╤════════╤═════════════════ │ NUMBER │ METHOD │OF CASES│ B. INFLUENZÆ │CULTURED│ FOUND ────────────────────────────────────────────┼────────┼────────┬──────── „ │ „ │ NUMBER │PER CENT ────────────────────────────────────────────┼────────┼────────┼──────── Nose culture │ 28│ 6│ 21.4 Throat culture │ 166│ 109│ 65.7 Sputum culture │ 28│ 17│ 60.7 Sputum (mouse passage) │ 76│ 61│ 80.3 Combined nose, throat and sputum cultures │ │ │ and sputum inoculation │ 28│ 28│ 100 Combined throat cultures and sputum │ │ │ inoculation │ 48│ 48│ 100 ────────────────────────────────────────────┴────────┴────────┴──────── Of any single method used the intraperitoneal inoculation of a white mouse with a specimen of the patient’s sputum proved the most efficient in demonstrating the presence of B. influenzæ. No single method served to demonstrate B. influenzæ in all cases, but by simultaneous cultures from the nose, throat, and deeper air passages no difficulty was met in showing that B. influenzæ was invariably present, usually in abundance somewhere in the respiratory tract during the acute stage of the disease. This result is not out of harmony with the rapidly progressive character of the attack upon the mucous membranes of the respiratory tract in influenza. Of interest in this connection are certain observations which suggest that the presence of B. influenzæ in predominant numbers at least is in many cases coincident with the acute stage of influenza and that the organisms show a tendency rapidly to diminish in abundance with the progress of the disease to recovery. In 82 cases of influenza cultured on the day of admission to the hospital, B. influenzæ was present in 52 (63.4 per cent) of the throat cultures. Repeated throat cultures in this group of cases from the fourth to the eighth day after admission when the temperature had fallen to normal, showed that B. influenzæ was still present in demonstrable numbers in the throat of only 25 cases or 30.5 per cent. Not only was there a material reduction in the number of patients in whom B. influenzæ could be demonstrated by the throat culture method, but the contrast in the predominance of B. influenzæ on the plates made early in the disease with those made during convalescence was often very striking. It is only fair to say, however, that some cases continued to carry B. influenzæ in their throats in large numbers throughout the period of observation.