H&MOLYS1NS. 55 



shows that the heating has not destroyed the entire 

 complement body, but only that part which effects 

 the digesting, solvent action. The part of the 

 complement concerned with the combination with 

 the inter-body or immune body, in other words, 

 that part called by Ehrlich the haptophore group, 

 must have remained intact. It is clear, therefore, 



zymotoxic group 

 COMPLEMENT 

 haptophore group 



IMMUNE BODY 

 FIG. 4. 



that anti-complements can only be formed when 

 there remain in the complements haptophore groups 

 that fit certain receptors in the organism of the 

 animal injected. From this it follows that the 

 complements consist of a combining haptophore 

 group which withstands heating to 55 C., and an- 

 other more fragile group which possesses the actual 

 solvent properties, and which Ehrlich calls the 

 zymotoxic group. There is a perfect analogy be- 

 tween this and the toxins already studied. These, 

 it will be remembered, consist of a haptophore and 



