In a study of a group of streptococci of Lancefield's Group A, biochemical characters, including fermentative reactions and sensitivity to bacteriophage, were investigated. It was observed that the strains of two of the sub-groups: (1) the lactose-deficient group (Evans, 1941) , and (2) the mannitol-fermenting group were not particularly sensitive to any of the 4 known types of streptococcic phage. It appeared likely that one or more new types of phage might be found if a search were made,

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... strains of streptococci of these two groups for the substrata. EXPERIMENTAL The methods used for the isolation of phage from sewage, and the techniques for the study of its characters, followed, with certain modifications, those previously described . Isolation. Samples of sewage collected for another purpose in February and March, 1940, from the final clean-out trap leading from hospitals to the city sewage system were studied. Samples from Baltimore, Boston, New York City, Evansville, Indiana, and Washington, D. C. were examined for phage which might be active against any of six selected strns of streptococci representing the two mentioned sub-groups.