large ones, an effort was made to divide the amebas into 

 equal parts. After more than 50 amebas had been treated 

 with cyanide, it was obvious that some unknown factor was 

 playing a part in the death of the organisms; for altho 

 the non-nucleated fragments usually succumbed first, there 

 were many conspicuous cases in v/hich the nucleated part 

 died much sooner. It seemed possible that the unknown 

 factor might be a difference between the anterior and 

 posterior end. The amebas v/ere divided v/hen they u^ere 

 moving along the bottom in the "limax" condition, and in 

 some cases the non-nuclear fragment was taken from, the 

 flowing anterior end, while in other c^ses it was taken 

 from the retracting posterior end. In order to determine 

 whether this made a difference, a number of amebas v/ere 

 divided in such a way th^t the nucleus remained in the 

 anterior half, while others were so divided that the 

 nucleus remained in the posterior half. 



The number of minutes which the nuclear and non- 

 nuclear fragments were able to withstand treatment with 

 cyanide is tabulated below: 



(57) 



