542 COLLECTED STUDIES IN IMMUNITY. 



contains a substance which kills trypanosomes, whereas this is not 

 present in the blood of other animals and cannot be produced in so 

 large an amount even by immunization. This might be the reason 

 why (aside from sleeping sickness of Central Africa) man is so refrac- 

 tory toward trypanosome infection. 



But if such a wealth of facts is disregarded in statements con 

 cerning " our certain knowledge," it must be admitted that a scientific 

 discussion is entirely out of the question, and had best be avoided 

 in the future. 



Furthermore, so far as conceiving the production of antitoxin 

 to be a secretion is concerned, I may say that this part of the paper 

 is nothing but another way of stating what I have always held. 

 Paltauf, 1 for instance, pointed this out to Gruber some years ago, 

 " In passing I may say that an ' escape ' of particles of protoplasm 

 into the blood really denotes a secretion." In an address delivered 

 in 1899 (!) I expressed myself in a way that shows that I have 

 always considered the production of antitoxin to be a secretory 

 process. 2 



" Or, s'il y a lieu de croire que les Antitoxines doivent leur origine 

 a une sorte de fonction secretaire des cellules et ne sont par conse- 

 quent nullement etrangeres a 1'organisme, le rapport specihque qui 

 les unit avec Jeurs toxines n'en devient que plus etrange." 



This point has been demonstrated especially by the researches 

 of Salomonsen and Madsen, and of Roux and Vaillard. 



But just this secretory character of antibody production is abso- 

 lutely at variance with the older view that antitoxins are merely 

 transformation products of the toxins. This was the view defended 

 by Buchner and held to be possible by Gruber even in his last attack. 

 It is just as impossible to believe that antitoxins arise from toxins 

 as it is to believe that lipase is transformed fat, or amylase, trans- 

 formed starch. 



Thus we see that the various points brought up by Gruber are 

 nothing but reproductions ot my views; the little that deviates is 

 incorrect or is based on misconceptions of an inflated knowledge 

 of the literature. 



Gruber's last two conclusions contain so little that is new that 

 it hardly pays to discuss them. For completeness' sake, however. 

 I shall append them. 



1 Weiner klin. Wochenschr. 1901, No 49. 



' This appeared only as an abstract in La Semaine Mddicale, 1899 



