22(; 



Rate of Growtfi of 

 til;: 



Tiihir 21. 

 the immimized and Non-Immunized Strains of Fibro- 

 sts for a f^eriod of Nineteen Passages. 



Peculiar in Ihis c-xpciimcnl. is [he increase in rate of 

 growth of the immunized si rain, instead of what was to 

 be expected, that the rate of growth of this strain should 

 be unaffected. It was, however, too constant a phenomenon 



