THE MECHANISM OF THE ACTION OF AMBOCEPTORS. 221 



plementoid, are still dissolved by the complements of dog serum. The source 

 of the dog serum complement was the fluid decanted from guinea-pig blood- 

 cells which, by treatment with active dog serum at 0C., had abstracted as 

 much of the amboceptor from the latter as possible. These experiments there- 

 fore show: 



1. That the complement of dog serum suffers a diminution of affinity in 

 changing to complementoid. 



2. That the complement present in guinea-pig serum possesses a weaker 

 affinity than the complement of dog serum with analogous action. 



