SPOTTED FEVER

Several methods for the experimental study of the rickettsial diseases have been applied to fièvre boutonneuse. An analysis of the results has indicated that fièvre boutonneuse is a variety of spotted fever and that the etiologic agent is a rickettsia which belongs to the genus Dermacentroxenus and to the species rickettsi (Wolbach (6)). The distinctive morphology of the organism and its characteristic intranuclear clustering in ticks and in tissue cultures are the important criteria upon which this conclusion is based. Immunological, histological, and cytological observations of a confirmatory nature are also reported.