PREFACE
The circumstances surrounding the publication of this paper call for an introduction. It constitutes a final report on an extensive investigation initiated by the late Dr. Silber C. Peacock. The work was carried out by him and by Miss Marie Werner throughout 1934 and 1935 and was completed in the two years following Dr. Peacock's death (on Jan. 3, 1936) by Dr. J. A. Bigler and Miss Werner. The investigation was a search for light on the incidence, distribution, specificity and clinical significance—in short, the epidemiology—of the hemolytic streptococcus and on its relation to scarlet fever, as revealed in a study of all of the personnel of the Children's Memorial Hospital and of all of the patients, both while they were in the hospital and after their discharge. Dr. Peacock had planned to carry on this line of investigation indefinitely. This plan was cut short by his tragic and