101 



Table 14. 



Table op Real and Calculated Haemolytic Indices 

 OF Serum Mixtures. 



The haemolysis produced by a mixture of sera is in about two- 

 thirds of the cases smaller than the average of the individual effects, in 

 contrast to the results obtained by Oernovodeanu and Henri. 



We have to admit that the isolysines produced by various animals of 

 the same species are different colloids and that they influence each other. 

 It is a well-known fact that colloid combinations have an optimum Of 

 eflBciency only if mixed in certain proportions, characteristic for the 

 nature of the components. It is possible that isolytic sera would also 

 show maximal effects when mixed in optimal quantities, the proportion 

 of which evidently is not 1 : 1 as in the abovementioned experiments. 

 But as the sera were mixed in this proportion, very likely not being the 

 optimal one the maximal effect could not be obtained from these mix- 

 tures. This might explain the variations in the differences between 

 real and calculated haemolytic index and the absence of a constant 

 mathematical relation between both. 



