Segregation of patients in wards according to type of bacterial infection while theoretically an improvement over the indiscriminate mixing of patients with many different types of infection presents many practical difficulties which make it impossible to carry out in the presence of an overwhelming epidemic. It is quite obvious that grouping of influenzal patients on the basis of the types of pneumococci that they carry in their mouths is impossible since the great majority of mouth pneumococci belong to Group IV and comprise a heterologous immunologic group. The separation of influenza patients who carry S. hemolyticus from those who do not would appear to offer a more hopeful field. Since we cannot make an immediate distinction between streptococcus carriers and noncarriers by inspection of the patient, this procedure requires the taking of throat cultures at time of admission to the hospital, the holding of patients for eighteen to twenty-four hours in receiving wards until the bacteriologic diagnosis has been made, and their subsequent distribution to streptococcus and nonstreptococcus wards. This is feasible when the admission rate is low and the number of streptococcus carriers found at time of admission is small. In the presence of an influenza epidemic it immediately becomes impossible to carry out in base hospitals as now constituted, since the demand for beds under such conditions at once converts a large part of the hospital into a group of receiving wards with little room remaining for subsequent separation of patients. The amount of bacteriologic work involved at once becomes prohibitive and the time required to make the bacteriologic diagnosis defeats its purpose since it allows the spread of hemolytic streptococcus to occur in the receiving wards during the interval.