The Loss of Hemolytic Capacity by a Fraction of a Culture of a Hemolytic Streptococcus without Change in Agglutination Characteristics

A culture of hemolytic streptococcus developed a non-hemolytic fraction which as determined by its agglutinogenic, agglutination, and agglutinin absorotion characters was identical with the hemolytic fraction, the only variation being one of function, or physiological action. This functional variation has proved permanent, as long as observed, for both fractions have continued to breed true. This study is offered as additional evidence in favor of the hypothesis that functional changes among bacteria are, at most, only very infrequently associated with changes in the antigenic matrix of bacteria.