Natural immunity against toxins 341 



wounds or from the absorption of venomous food. The theory of [358] 

 the insusceptibility of the cells of animals naturally refractory to 

 toxins must also be rejected ; it is incompatible with well-established 

 facts. Nothing remains, then, but to assume that the formed 

 elements are the principal factors in this natural immunity, and that 

 they interpose to prevent the passage of the poisons towards the 

 very susceptible nerve cells. 



