18 (i 88) Society for Experimental Biology and Medicine. 



host. Like the piroplasma, the infective agent passes into the egg 

 and is inoculated by the larvas. Theiler believes that this spi- 

 rocheta is a parasitic protozoon. 



Two English observers, Dr. Todd and the late Everett Dutton, 

 have found that the tick fever, or at least some cases of tick fever, 

 are associated with the presence of spirochetas in the circulating 

 blood. They believe that tick fever is clinically identical with re- 

 lapsing fever, and that its pathogenic agents are spirochetas, which 

 they consider are probably identical with the spirochetas of re- 

 lapsing fever, as described by Obermeier. They believe that a tick, 

 Ornitliodorus moubata, transmits the spirillum from animal to ani- 

 mal, since they have seen the disease conveyed to a monkey by a 

 tick, and they have evidence that young ticks, after their first feed- 

 ing, if bred from infected mothers, are able to transmit the disease. 

 They have not been able to trace the spirilli in infected ticks further 

 than the stomach and malpighian bodies. In the light of Mar- 

 choux and Salambeni's work, upon the transmission of the spir- 

 illum disease of fowls by ticks, Ross considers it probable that 

 the disease in man is also inoculated by infected ticks. 



It is unnecessary to enter at this time into the discussion of the 

 protozoon nature of this interesting group of organisms, except to 

 recall that Schaudinn believed there is little doubt that the spi- 

 rochetas of relapsing fever and of the septicemia of geese will be 

 shown to be trypanosomes, and hence unrelated to the bacteria. 

 Novy and McNeal, it will be remembered, have shown, in a com- 

 munication to this society, 1 that Schaudinn's interpretation of what 

 he has seen is subject to grave doubt. The spirochetal forms of 

 the trypanosomes depicted by Novy and McNeal, have not the 

 slightest resemblance either to the organisms of this case or to 

 Obermeier's or Sacharoff's spirilli, as shown by the photographs 

 of the latter. The question as to the identity of the organism of 

 this case, with that of the spirillum of Obermeier cannot be settled 

 off-hand. On account of the great variety in the clinical symptoms 

 of the reported cases of relapsing fever observed during the epi- 

 demics, it is perhaps unreasonable to draw any conclusions, either 

 for or against the identity of the organism of this case with that of 

 relapsing fever. 



1 Proceedings of this Society, 1904-05, ii, p. 23. 



