RESEARCHES ON CERTAIN PROBLEMS OF PLAGUE IMMUNITY 2/ 



TABLE XVIL 



TESTING SERUM OF " Pr." ON MICE. 



The Serum injected subcutaneously at one side of the body, and 24 hours 

 later the Toxin at the other side. 



Test Toxin No. 10 about 4 to 6 M. L. D. 



Only small mice available. 



Controls: — With Serum of "B." (old Diphtheria Horse). 



(137) 



