72 IMMUNE SERA. 



tion of the precipitin. This is entirely analogous 

 to the anti-hsemolysins, the anti-spermotoxin, etc. 

 If rabbits are treated with rabbit serum, a serum 

 is obtained which will, in certain cases, precipitate 

 the serum of other rabbits. This was done by 

 Schiitze, and he called this serum iso-precipitin. 



