PROTOCOLS OF EXPERIMENTS 



89 



Experiments with Box XXXIV lice 



Between feedings the box was kept in an incubator at a 

 temperature varying from 20 to 30 C., usually 29 C. The 

 box contained 30 W lice (30 nymphs). 



From these lice the following preparations were made: 



Louse No. 



1 



Excreta 

 Eggs 



Sections Wll 1 

 Wll* 



Result of Microscopical 

 Examination 



Rickettsia absent 

 Rickettsia absent 



Rickettsia absent 

 Rickettsia absent 



Rickettsia absent 

 Rickettsia absent 



Rickettsia absent 

 Rickettsia absent 



Result of Animal Inoculation 



Guinea-pig 36; Temp. 

 Did not react to blood from a typhus patient 

 Guinea-pig 37; Temp. 

 Proved susceptible to blood from a typhus 

 patient 



Guinea-pig 38; Temp. 

 Proved susceptible to blood from a typhus 

 patient 



Guinea-pig 39; Temp. 

 Experiment complicated by pseudo-tuber- 

 culosis, but proved susceptible to blood 

 from a typhus patient 



