Ml 



»c) and Fischer i!*!) scorn lo confirm it. The conchlions 

 under which the differenlialion lakes place in vitro ai-c 

 nol yel known. Il does nol oeciii- in all ciilliires oF lai-<^e 

 mononuclear leucocyles. ])ut mainly in those whit-li i^row 

 verv slowly. 



