448 



COLLECTED STUDIES IN IMMUNITY 



was made by mixing 1 cc. of a hot, saturated solution of cholesterin 

 in methyl alcohol with 9 cc. hot 0.85% salt solution. This homo- 

 geneous suspension of cholesterin served as stock solution for the 

 experiments. 



TABLE IV 



0.25 cc. GUINEA-PIG SERUM AND THE INHIBITING SOLUTION ARE DIGESTED 



AT 37 C. FOR THREE-QUARTERS OF AN HOUR. THEREUPON THE Ox 



BLOOD +0.01 1% COBRA VENOM ARE ADDED. 



TABLE V. 



These various experiments lead us to believe that serum comple- 

 ment and lecithin arc two entirely distinct substances. On the other 

 hand the complementing property of the serum for cobra venom 

 corresponds so well with the other complement functions of the 

 sera that no reason at present exists for undertaking a separation. 

 In conformity with this correspondence we find that the activating 



