H&MOLYSINS. 51 



of the same organism. The formation of these 

 auto-anticomplements, according to Ehrlich, can 

 only be explained by assuming that in normal goat 

 serum there are present complements which are 

 almost identical with those of the rabbit serum, 

 but which differ from them in that they find recep- 

 tors in the rabbit serum whose haptophore group 

 fits to their own. 



Fluctuations in the Amount of the Active Substances 

 in Serum. As already said, we have thus far been 

 unable to show that the complements of an organ- 

 ism are decreased through the action of spontane- 

 ously formed anti-complements. We have, how- 

 ever, come to know certain conditions under which 

 there may be a decrease of certain complements in 

 normal serum. Ehrlich and Morgenroth showed 

 that in rabbits poisoned with phosphorus and in 

 whom, therefore, the liver was badly damaged, the 

 serum on the second day (the height of the disease) 

 had lost its power to dissolve guinea-pig blood, 

 and that this was due to a disappearance of the 

 complement. Metchnikoff also reported that in an 

 animal suffering from a continuing suppurating 

 process the complement had fallen considerably in 

 amount. Especially interesting are the experi- 

 ments of v. Dungern, who showed that animal cells, 

 hence emulsions of fresh organs, are able to attract 

 and combine with complements. 



Fully as important as the question of a decrease 

 in complements or an inhibition of their action, is 



