T HIS STUDY of cultures from a group of individuals of approximately the same age but from various localities was undertaken in an endeavor to collect statistics on the number of carriers of B. diphtheriae, which might be present in such a group, and to correlate the distribution of such carriers with the localities where diphtheria had been endemic.In the routine physical examination of persons entering the university, the nose and the throat are examined in order that an exact record of the physical condition of each entrant may be obtained. The physical examinations are made early in the first week of university exercises so that it is scarcely to be expected that a student may have picked up organisms of diphtheria from other students, i.e., the nasal and pharyngeal flora would be typical of pre-ulniversity associations.Nose and throat swabs were taken in the usual way. A sterile swab was applied to the tonsillar region on each side and swept over the pharynx. A second sterile swab was inserted first into one nostril and then into the *other. A numerical record was kept of each set of swabs, cards with duplicate numbers being filled out by the entrant, giving his name, college address, and home address. In the late afternoon the swabs, collected during each day, were rubbed over the surface of Loeffler's blood serum slants, the nose and the throat swabs from each individual being rubbed over the same slant. The tubes were incubated for 18 * Report of an experiment carried on in the Department