ANTITOXINS 25 



poisonous toxoid and then, an hour later, with 

 tetanus toxin. He found that much more toxin 

 was required to kill this animal than a normal 

 guinea pig of equal size. When, on the contrary, 

 he waited one to three days, it was found that then 

 a dose of tetanus toxin which would not even 

 tetanize a normal guinea pig was sufficient to kill 

 this one. 



It will be seen that in the above experiments 

 the completely non-poisonous toxoid, although it 

 effected an increased production of receptors, did 

 not cause their thrusting-off. The serum of the 

 rabbit treated with toxoid contained no antitoxin 

 whatever. Wassermann concludes from this and 

 other experiments that the thrusting-off cannot be 

 a function of the haptophore group, and that 

 something additional is required. This " some- 

 thing," he claims is a function of the toxophore 

 group. It may be stated that Von Dungern has 

 also published experiments (with majaplasm) point- 

 ing to the existence of the second stage, the stage of 

 sessile receptors. 



Antigens or Haptins. It has been found that 

 it is impossible to produce any immunity against 

 all poisons, e.g. strychnine or morphine. Accord- 

 ing to Ehrlich these simpler chemical molecules do 

 not enter into a true chemical combination with 

 the tissues, but form rather a kind of solid solution, 

 a loose combination with the cells, so that they can 



