IMMUNITY. 331 



to tetanus it would seem from this as if some 

 component derived from the tetanus bacteria 

 were present along with the anti-substances. 

 Similarly Marcuse observed in a child after 

 the injection of diphtheria serum the appear- 

 ance of paralysis of just such a character as 

 would be produced by diphtheria toxin. 



But on the other hand an important fact 

 lends countenance to the view that the cells of 

 the human or animal organism which forms the 

 anti-substance are the more important factors. 

 If we administer a given quantity of toxin in 

 the form of many small doses one after another, 

 and in another instance inject the same quan- 

 tity all at once in one large dose, the amount 

 of antitoxin found in the animal after the same 

 lapse of time is considerably larger in the 

 first case than in the second. (Roux.) The 

 numerous small stimuli are in this case able 

 to act cumulatively upon the body-cells con- 

 cerned in the formation of the antagonistic 

 substances, while by the other method a great 

 part of the single large dose of foreign active 

 proteid is at once eliminated. If it were a case 

 of simple chemical combination, the total 

 quantity of antitoxin formed would neces- 

 sarily be the same in both cases in the same 

 period of time. The toxins therefore act as 

 stimuli upon the body-cells, and these forth- 



