66 SPECIFICITY OF RICKETTSIA PROWAZEKI 



Record of Guinea-pig 15, inoculated with the viscera of 

 rickettsia-infected louse W 228 



The temperatures following inoculation on May 15th were as 

 follows: 



F. P. 



May 15 102.4 May 22 104.0 



B 16 102.6 23 103.1 



" 17 102.1 24 104.4 



a 18 102.4 25 104.4 



" 19 103.0 " 26 104.8 



" 20 102.7 27 105.2 



21 103.1 28 105.0 



May 28th; killed. The spleen was markedly enlarged and 

 covered with a thin transparent fibrin-like layer. All other tis- 

 sues were negative. 



The brain lesions characteristic of typhus were found upon 

 histological examination. 



Result: Guinea-pig 15 developed typhus after inoculation 

 with viscera from louse W 228 after an incubation period of 

 eight to ten days. The infection was proved by histological 

 examination. 



Conclusion: Rickettsia-infected louse W 228 contained the 

 virus of typhus. 



