INDIAN FORM OF RELAPSING FEVER. 193 



Filially, from a consideration of the work performed by other inves- 

 tigators and from my own experiments, carried on with all these 

 different strains of spirochgetge, including a study of the morphological 

 characteristics, serum reactions, and animal inoculations, it appears to me 

 that the African and European strains of spirochgetse are distinct species. 

 However, it does not yet seem clearly demonstrated that the American 

 and Indian strains are distinct from the European; if not identical, 

 these strains must certainly be very closely related to one another. 



