﻿STUDIES IN PLAGUE IMMUNITY. 175 



certain of the agglutinative experiments and in the preparation of aggress- 

 in exudates, under which subjects the technique of the inoculations is 

 described. 



In testing the immunity of all the animals care was taken to introduce 

 the infection upon the opposite side of the body to that upon which 

 the vaccination or prophylactic injection had first been made. This 

 precaution was taken in order to avoid any chance of obtaining results 

 which might have been influenced by the presence of a local immunity 

 which had developed in the animal, particularly in the tissues about the 

 point where the first inoculation had been made. Wassermann and 

 Citron 3i have recently called special attention to the local development 

 of immune bodies. 



M Ztschr. f. Hyg. u. Infectionskrankh., Leipz. (1905), 53, 331. 



