ViTien the nucleus was in the anterior end, the non- 

 nuclear fragment died first in 1^ cases, the nuclear 

 fragment died first in ? cases, and in the remaining 4 

 cases each part disintegrated at about the same time. 

 When the nucleus was in the posterior end, however, the 

 nuclear fragment was never the first to disintegrate: the 

 death of both fragments occurred at the same time in two 

 instances, and in the remaining 22 cases the non-nuclear 

 fragment was the first to disintegrate. The complicating 

 factor is now understood. The anterior end of Araeba is 

 more susceptible to cyanide than the posterior end. 

 Essentially the same conclusion was reached by Miss Hyman 

 (1917) in an investigation of the metabolic gradient in 

 Ameba. 



V«hen the non-nucleated half is taken from the poster- 

 ior end, its greater susceptibility to cyanide is not 

 very definite because of the difference which exists be- 

 tween the anterior and posterior parts. When this dis- 

 turbing factor is removed, however, by cutting the non- 

 nuclear fragment from the anterior end, the non-nuclear 

 fragment is seen to be much more susceptible to cyanide 

 than the nuclear fragment. 



(^9) 



