ON SPECIFIC THERAPEUTICS. 21 



special kind of amboceptor arose, there would be 

 no complement available, all having previously 

 been used up for the action of indifferent ambo- 

 ceptors. It is thus owing to the fact that the 

 complement is free or only loosely united to the 

 amboceptors in the circulation, that at a given 

 moment it is ready for use. The maximum 

 stimulus to action is rendered possible by the 

 anchoring of the amboceptor to the erythrocyte, 

 the avidity of the former toward the complement 

 being thus increased. This increase of avidity 

 which consists in the chemical affinity of the 

 complementophile group for the complement 

 being carried to its maximum, represents the 

 gist of our knowledge of the action of the 

 amboceptor. 



The amboceptor, therefore, exercises the 

 important function of bringing about a specific 

 modification of those conditions existing in the 

 organism which determine the distribution of 

 complements, and which otherwise are not very 

 evident. It causes the complements to become 

 monotropic by its union with the given sub- 

 stance. The complements are thus localised 

 by amboceptors which have previously become 

 united to the substance cell or otherwise. At 

 the same time this action represents a purposive 



