82 PROPERTIES OF ELEMOLYTIC SERA 



///. Immune-body to Ox's Corpuscles (obtained by injecting 



the Eabbit). 



It will be seen from the tables above that the dose of 

 immune-body is practically the same with guinea-pig's 

 as with rabbit's complement. The dose of the latter com- 

 plement is the higher, and in a previous section (p. 45), 

 it was shown that this was probably due to a smaller number 

 of complement molecules in a given volume of serum, 

 rather than to a weaker action of the zymotoxic group. 

 The combining relationships of the two complements have 

 also been fully discussed there, so that it is unnecessary 

 to repeat the results obtained. It is sufficient to say that 

 they behave as regards combination in haemolysis pretty 

 much as if they had the same haptophore groups. We 

 shall refer merely to the action of ox*s complement along 

 with the above immune-body. 



With this combination it is usually impossible 1 to produce 

 more than a fraction of lysis in the corpuscles (usually not 

 more than a tenth), no matter how large amounts of immune- 

 body and complement are used ; in only one case did we 

 get a considerable amount of lysis, about three-fourths. 

 We never obtained complete lysis, however. In other 

 words, the ox's serum does not ' complement '. Is this 

 due to want of combining power of the ox's complement, 

 or to the deficiency of toxic action ? This question can 

 be answered by finding the amount of complement taken 

 up when varying amounts of immune-body are used. 



The scheme is : 



Ox's O + n IB -f- x ox's C guinea-pig's O + IB. 



1 This applies only to cases where the immune-body and the comple- 

 ment are added at the same time to the corpuscles, as is the usual pro- 

 cedure. If, however, the immune-body be added to the corpuscles an 

 hour before the complement, lysis of the corpuscles sometimes results 

 (vide, p. 87). 



