Further Studies on the Serological Classification of Haemolytic Streptococci

In a preliminary paper (1926) I have shown that most strains of haemolytic streptococci obtained from scarlet fever may be placed in two very definite serological groups. The strains from 119 cases were found to belong to Type I, from 57 cases to Type II, while from 34 cases the strains were un-identified. That the scarlatinal streptococci do not form one serological group has been confirmed by Griffith (1926) and by James (1926). Further, the sera and type cultures used in this investigation have been interchanged with those of Dr Griffith, and his Types I and II strains have been found to conform with the main serological types found in Aberdeen.