ALEXIN ABSORPTION. 



411 



heated rabbit serum deprived of its sensitizer by contact with goat 

 corpusles is added.* The alexin is then added as to the first series. 



Controls are also made without any sensitizer, either normal or 

 immune, to prove the necessity of its presence for the production 

 of hemolysis. 



In the following table is shown the length of time in minutes 

 required for complete hemolysis at 35 C. The letters "M," "SI" 

 and "Nul" indicate that after several hours hemolysis is marked, 

 slight or none, as the case may be. 



OCCURRENCE OF HEMOLYSIS. 



In the mixtures containing salt solution but no antagonistic serum 

 we may estimate the relative potency of the two sensitizers; we 

 find, for example, that 0.005 of a cubic centimeter of immune serum 

 affects the corpuscles as much as a relatively large dose (0.2 of a 

 cubic centimeter) of normal rabbit serum, and that 0.01 of a cubic 

 centimeter of immune serum sensitizes a little better than does 0.4 

 of a cubic centimeter of normal serum, and so forth. It is further 

 to be noted that the antagonistic serum (deprived of sensitizer) 

 retards hemolysis approximately equally in corpuscles sensitized 

 to the same degree by normal or by immune serum. 



* To the sediment of 5 c.c. of washed goat blood 5 c.c. of rabbit serum, 56 

 degrees, was added. A few hours later the mixture was centrifugalized and the 

 supernatant fluid removed. 



