THE COMPOUND H^EMOLYSINS 



251 



mime-body, c is the quantity of antialexin necessary to 

 reduce the quantity of haemolysin to the eighth part of 

 that necessary for total haemolysis, which nearly corre- 

 sponds to the limit of observable haemolysis. 



INFLUENCE OF ANTIALEXIN ACCORDING TO THE LAW OF MASS-ACTION 



Here we observe that for a certain quantity of immune- 

 body (a =40 ; b = 10), when the immune-body and the alexin 

 are present in equivalent quantities, c passes through a 

 minimum ; for higher values of a, c increases with a and 

 tends to reach proportionality with a as a attains very high 

 values; for lower values of a, c increases with b. In 

 other words, the addition of a given quantity of antialexin 

 has a maximal influence when a 40, and the haemolytic 

 action is reduced to a lesser degree for values of a above 

 or below 40. The general behaviour will be the same even 

 if the affinity of the immune-body for the alexin is not 

 equal to that of the antialexin for the alexin, only then 

 the minimum of c is displaced. 



If we now compare this last general table with those of 

 Sachs and Morgenroth, we observe that all of them may 

 very easily, within the errors of observation, be regarded 

 as special cases of the general table ; while they conclude 



