BACTERIOLYSIS AND ALLIED PHENOMENA 155 



is removed, and the supernatant fluid will still reactivate the action 

 of heated immune serum on rabbit's corpuscles. This is not the 

 invariable rule, and in other cases the non-dominant complements 

 are not seized until the dominant has been anchored. In either 

 case we can see an alternative explanation for the facts observed 

 by Bordet and Gengou. Ehrlich points out that the presence of 

 the power to bring these many ferments into relation with the 

 giant molecule of the protoplasm must be of advantage in cell 

 nutrition, as enabling the greatest possible effect to be produced, 

 and quotes Hoffmeister as showing that the liver cell contains ten 

 different ferments, and Delbruck as attributing five to the yeast 

 cell. 



The discovery that the haemolytic action of snake venom 

 depends on the mechanism of amboceptor and complement made 



FIG. 36. SHOWING EFFECT OF ADDITION OF RABBIT'S CORPUSCLES TO THE 

 SERUM SHOWN IN FIG. 35. 



The amboceptor unites with the corpuscle, and all the complements are with- 

 drawn. The supernatant fluid loses its power of dissolving ox corpuscles 

 previously sensitized. (See also Fig. 37.) 



by Flexner and Noguchi, and the excellent subsequent work of 

 Kyes, made us realize that the process might be even more 

 complex. Flexner and Noguchi "^showed that snake venom 

 contains two substances, one of which is thermostable, not being 

 destroyed at 90 C., and which in itself has no power of bringing 

 about solution, and which is evidently equivalent to amboceptor. 

 It may be reactivated by the other thermolabile substance or by 

 the complements of normal serum. For example, horse corpuscles 

 can be dissolved by heated venom and fresh ox serum, ox blood 

 corpuscles by heated venom and guinea-pig serum, and so on. 

 Kyes found that some corpuscles, washed from all trace of 

 serum, could be dissolved by cobra venom alone ; others required 

 the concomitant presence of fresh serum of the same or other 

 species. Thus the corpuscles of man, the dog, guinea-pig, etc., 

 are dissolved by the venom alone, whilst those of the ox, sheep, 

 and goat are not. He formed the theory (for reasons which will 



