TOXINS AND ANTITOXINS. 27 



his pupils have been able to show that the toxins 

 introduced into certain cold-blooded animals 

 (Oryetes nasicorius) may remain for several months 

 without alteration in their circulation. 



If we consider the facts of the theory of Ehrlich's 

 lateral chains, which we have mentioned, we are 

 led to well-defined conclusions regarding the mode 

 of action of the toxins. In fact, since these toxins 

 exhibit a pronounced chemical affinity for the tis- 

 sues, and while, on the other hand , they can attach 

 themselves only because of the presence of certain 

 functional groups of the protoplasmic molecules, 

 this union can take place only in certain specific 

 centers. This has been fully confirmed by experi- 

 ments in vitro. 



It is known, since the researches of Ehrlich,* 

 Wassermann and Takaki.f Marie, J Metchnikoff,§ 

 and a host of other scientists, that this fixation is 

 due to a clearly elective property. It is for this 

 reason that the tetanus toxin fixes itself only upon 

 the nervous tissue, and that in this action all passes 

 as if the nervous tissue had been provided with 



* Ehrlich: Berl. Klin. Woch., No. 12, i8g8. 



f Wassermann and Takaki; Berl. Klin. Woch., Med., p. ^, 

 1898. 



t Marie: Sur les Proprieties Antitoxiques aux Centres Ner- 

 veux de 1' Animal Sain. Ann. Inst. Past., 1898, p. i. 



§ Metchnikopp: Recherches sur I'lnfluence de rOrganism 

 STjr les Tpxines. Ann. Inst- Past., 1899, p. 82. 



