Review of the Observations which have Accumulated with regard to the Significance of Diphtheria Types in the Last Four Years (1931-1935): (Section of Pathology).

1. In a series of more than 6,000 cases of diphtheria gathered from many parts of the country and from Germany during the last five years, at least 95% of the strains have fallen within three principal types described in 1933 as Gravis, Intermediate, and Mitis.2.