88 



Discussio7i. 



515 and 516 were injected at the same time and with the same 

 serum of the same mules (516 had' one injection more). The haemoly tic 

 index in 516, however, appeared to be much lower. 



Conclusion. 



The sera of all three donkeys injected with mule serum were 

 haemoly tic for horse and mule blood. 



