DEVIATION OF COMPLEMENT 141 



gave only a very slight, in fact rather doubtful precipitate, 

 whilst 0-000,01 c.c. gave no trace of precipitate. 

 Table 3 shows the action of our third serum. 



Anti-serum, rabbit v. guinea-pig. 



Test for complement = 0-5 c.c. suspension of ox's corpuscles treated with 

 immune-body. 



TABLE 3 



Babbit's complement 



In this case the anti-serum alone has a slight though 

 distinct effect on the haemolytic action of rabbit's comple- 

 ment ; this is probably due to the fact that rabbit's and 

 guinea-pig's sera contain a few common receptors. The 

 addition of even 0-000,01 c.c. of guinea-pig's serum 55, 

 however, gives a marked deviation phenomenon. This 

 experiment is of special interest as the anti-serum used gave 

 practically no precipitate when added to the homologous 

 serum ; even 0-01 c.c. of the latter produced merely a faint 

 cloudiness but no real precipitate. 



2. ON THE DEVIATION OF DIFFEKENT COMPLEMENTS 



It can be readily tested by the above methods whether or 

 not any given complement is taken up by a particular com- 

 bination of serum + anti-serum. Moreschi found that a 

 number of different complements may be deviated by the 

 same combination, or, as he expresses it, an anti-serum 

 becomes anti-complement to the complements of different 

 animals on the addition of a small quantity of the homolo- 

 gous serum. Our observations are confirmatory of this, 

 but they show also that some complements may not be 

 deviated. The red corpuscles used in testing for comple- 



