COMPLEMENT AS AGGLUTININ 89 



same substance. A study of the temperatures at which the 

 two effects agglutination and lysis occur, shows that a 

 slight difference exists. This may be due to there being 

 what we may call two complements, or it may simply be due 

 to one substance exerting the agglutinating effect at the 

 lower temperature. Further observations will be necessary 

 on this point. It is also to be noted that the production of 

 adhesiveness of the corpuscles may be manifested before 

 agglutination in the ordinary sense appears. 



The facts noted show that the phenomenon of agglutina- 

 tion usually produced by a single body (agglutmin) possessed 

 of combining and agglutinating groups, can also result from 

 the co-operation of two substances in a manner completely 

 analogous to what is seen in bacteriolytic and haemolytic 

 action. Whether this agglutination of an animal's cor- 

 puscles by its own complement may be brought about in 

 conditions of disease by some substance acting like an 

 immune-body remains to be seen. If it does, it is manifest 

 that very grave effects will result. 



