10 SECTION 1. HYGIENIC MICROBIOLOGY AND PARASITOLOGY. 



seems, therefore, certain that some or all of the cells in the area in the 

 subcutaneous tissues that the toxin reaches must take part in pro- 

 ducing antitoxin. If toxin is injected through the trachea into the 

 lungs it acts in the same way as when injected subcutaneously. I 

 have seen similar, though not as definite, results with the injection 

 of various bacterial antigens. These facts seem to suggest that 

 more varied cells than Dr. Gay indicates may take part in antibody 

 formation. 



Dr. VAUGHN thinks that the ferment is formed by different cells 

 according to the sensitizer used. He referred to the work of J. W. 

 Vaughan on sensitization to cancer proteins in which it appears 

 that the ferment is formed in the large mononuclear leucocytes and 

 that the sensitization is transitory. The fact that the nonpoisonous 

 part sensitizes may be due to the presence of a minute trace of un- 

 broken proteins. However, this seems highly improbable because 

 * this part does not sensitize to itself. 



O 



