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LECTURES ON IMMUNITY 



into their two constituents has been proved for more cases 

 than the coagulating action of rennet (and other casein- 

 coagulating substances, lactoserum included, cf. Chapter 

 IX). 



Just in the same manner as tetanolysin behave other 

 lysins of bacterial origin. For streptolysin produced by 

 streptococcus Madsen and Walbum have found the follow- 

 ing figures of the toxicity (q), after the addition of n c.c. 

 of antitoxin to a given quantity of poison. The calcu- 

 lated figures are obtained under the assumption that i c.c. 

 of the antitoxin solution used is equivalent to 4.8 times the 

 used quantity of lysin. The constant of equilibrium is 

 ^=0.13 at 20 C, very nearly like that for tetanolysin. 

 TOXICITY (q) OF STREPTOLYSIN AFTER ADDITION OF n c.c. OF ITS ANTILYSIN 



The observed figures are mean values from three dif- 

 ferent series of observations. The agreement between the 

 observed and the calculated values is nearly perfect until 

 n^ is about 1.5. At high values of n the observed toxicity 



