A general health survey was made of 1,392 children of school and pre-school age in a typical Ontario town and an adjoining rural township. This included intracutaneous tuberculin tests and single X-ray films of the chest. Four hundred and twenty-six children, or 32 per cent., reacted to tuberculin; 14 children, practically 1 per cent., were considered to have active tuberculosis. Thirty-six per cent, of town children reacted, and 22 per cent, of the rural children. In the general grouping approximately 15 per cent. react at time of entering school. At 7 years 25 per cent. react, at 10 years 40 per cent, react, and at 15 years 50 per cent, are infected. Up to the age of 10 the incidence of infection is the same for boys as for girls. In the age group 10 to 14, the incidence rises more rapidly in girls in the town and in boys in the country. From a comparison with other studies it is quite evident that infection is not as great in rural and small town communities as in the large cities. Radiological studies of the chests of reacting and non-reacting children have given results in accord with the conclusions of the special committee of the National Tuberculosis Association presented at the 1922 meeting (see American Review of Tuberculosis, July, 1922, vol. vi, 531). A diagnosis of lymphatic tuberculosis or even of early pulmonary tuberculosis is not warranted by a study of X-ray films alone. In a large percentage of cases giving a history of respiratory infections there was evidence of increased density in the hilum and larger trunk shadows, simulating those of tuberculosis. Of the reactors, 36 per cent. had shadowing within normal limits, and 64 per cent, showed increased shadowing. Of the non-reactors, 56 per cent, had shadowing within normal limits and 44 per cent, showed increased shadowing. This is one of a number of provincial surveys being conducted in Canada, the results of which will be published by the Canadian Tuberculosis Association.