It was noted previously by Pilot and Davis 1 that the incidence of hemolytic streptococci was less in the oropharynx of tonsillectomized that in the nontonsillectomized, the organisms occurring in 15.8% in few numbers in the former group as compared with 58% in larger numbers in the latter group. Nichols and Bryan 2 reported the disappearance of these organisms from the throat in 27 of 31 patients 11 days after extirpation of diseased tonsils. Simmons and Taylor 3 noted the streptococci in fewer numbers in a somewhat larger percentage (23%) after tonsillectomy. Tongs4 found these streptococci in 5% of tonsillectomized persons as compared with 60% of the cultures of the surface of the tonsils of the nontonsillectomized. Van Dyke 5 obtained positive cultures in 16.4% of tonsillectomized persons, mostly adults. In all of these investigations cultures were made of the pharynx or the region of the tonsils, and studied with special reference to the incidence and numbers of hemolytic streptococci. In all it is quite evident that tonsillectomy reduces considerably the frequency of Streptococcus hemolyticus. As no nasopharyngeal cultures were made, a study was undertaken of the flora of the nasopharynx with reference to the pneumococcus and the influenza bacillus, as well as the hemolytic streptococcus in children whose tonsils and adenoids had been removed, and a comparison made with a similar group in which tonsils and adenoids were present. The investigation was carried out from September to December, 1920.