THEORIES OF IMMUNITY. 



(and in the bacterial cell molecule in certain 

 cases) that exerts the poisonous action on 

 the cell, or is neutralized by the antitoxine. 



Toxines : the powerful poisonous substances 

 elaborated during- the growth of many bac- 

 teria; the soluble toxines are those remain- 

 ing in the filtrate of fluid cultures of some 

 bacteria. 



Toxoids: the less poisonous substances remain- 

 ing in a filtered culture when this has been 

 kept for some time, and after the soluble 

 toxines have disappeared. 



Toxones : supposed by Ehrlich.to exist along with 

 toxines and toxoids and possessing hapto- 

 phorous atom-groups having a less strong 

 affinity for similar groups in antitoxine 

 or cell than toxine: capable, however, of 

 combining with antitoxine, and of pro- 

 ducing very slow poisonous results (e.g., 

 diphtheria paralyses). 



Vital nucleus: Ehrlich's term for his conception 

 of a centre of vital activity existing in the 

 protoplasm of the cell, with which are asso- 

 ciated the special cell capacities. 



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