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TH. THJ0TTA AND ODD FALSEN SUNDT 



The experiment seems to show a distinct protective action 

 of the antiendotoxin serum against its homologous toxin, while 

 the control tests with endotoxin and antiexotoxin serum did 

 not show protection. It seems therefore justifiable to consider 

 the toxic effect of the extract of the dysentery bacilli (the "endo- 

 toxin") as a specific action due to the endotoxins of the dysen- 

 tery bacillus rather than to a non-specific protein toxicity. 



In the tests with exotoxin we did not find any distinct neu- 

 tralization of the toxic effect of the broth injected. This fact 

 might be due to the short period of immunization of our serum 



