ANTI-JELEMOLYSINS 



457 



unagglutinated bacteria; (2) certain sera are able to agglutinate 

 the corpuscles of one species without effecting their haemolysis, 

 and to both agglutinate and hsemolyse the blood of other species ; 

 (3) agglutinins are more resistant to heat than hsemolysins, so 

 that, if a serum containing both, be warmed to 55 C., the 



FIG. 24. Keceptors of the Second Order (Ehrlich's theory) ; the letters 

 refer to the same Structures as in Fig. 22, B representing the Zymophoric Group 

 of the Keceptor, and P the Agglutinated Body. 



haemolytic power will disappear (vide supra), but it will still 

 agglutinate. 1 



We are now in a position to study the various substances in 

 which hsemolysins and agglutinins naturally occur, and for this 

 purpose, it will be most convenient to study them according to 



1 It is possible that the same substance in different concentrations may have 

 a different action. (Editor's Note.) 



