Chemical Basis of Genus and Species 57 



be illustrated by the following table from Nuttall. 

 The antiserum used for the precipitin reaction was 

 obtained by treating a rabbit with human blood serum. 

 The forty-five bloods tested had been preserved for 

 various lengths of time in the refrigerator with the 

 addition of a small amount of chloroform. 



TABLE II 



Quantitative Tests with Anti-Primate Sera 



Tests with Antihuman Serum 



