Lack of Correlation, among Meningococci, between Serological Grouping and Lethal Effects on Rabbits.

The differentiation of meningococci into distinct serological groups on the basis of their tropin reactions (Evans, I920) raised a question as to what extent such serological distinctions may be correlated with the protection afforded rabbits by the intravenous injection of strains of a given group against strains of another group. A series of experiments relative to this question has been carried out, and the results are presented in this paper.