Nasal sinus disease in young children assumes in my mind increased significance each year. The more the nasal sinuses of young children are investigated at autopsy, the more is one impressed with its significance. In children who die from conditions not associated with emaciation or marked malnutrition, the observations are very instructive. The presence of an unsuspected chronic infection of the ethmoidal labyrinth or of the maxillary sinuses is not an uncommon observation. The relationship of the sinuses to the proper respiratory tract is quite comparable to that of the middle ear. Each opens directly into the upper respiratory tract. One is as often infected as the other. The ear is connected with the pharynx by a tube; the sinuses open by windows into the nose. Swelling of the mucosa easily blocks the eustachian tube, interfering with drainage and producing symptoms which direct attention to the ear. The same amount