INCUBATION AND DURATION 

 TABLE XI 



149 



may have been due, as da Rocha-Lima believes, to a massive 

 infection from the louse. The record of this guinea-pig is 

 shown on page 65, under "Experiments to prove the Specificity 

 of Rickettsia prowazeki for Typhus." 



The incubation periods following intraperitoneal injections 

 of blood from man (five patients) to guinea-pig (28 animals) 

 were as follows (Table XII) : 



TABLE XII 



Number of 

 Incubation Guinea-pigs 



9 davs . . 2 



Number of 

 Guinea-pigs 



Incubation 



16 days 5 



10 

 11 

 12 

 13 

 14 

 15 



17 

 18 

 19 

 23 

 25 



3 

 1 

 1 

 2 



_1 

 28 



The incubation periods following inoculations from guinea- 

 pig to guinea-pig (passage virus) are shown in the following 

 table (Table XIII): 



