346 Mot tier . — The Effect of 
plasts and the inclusions. Consequently the movement was 
first inhibited by placing the sections, properly fastened upon 
a slide, in water containing from 3 to 5 °/ o ether. When all 
movement had ceased, the preparations were transferred to 
water containing just enough ether to prevent a return of the 
movement, in which they remained during centrifugal action. 
(It may be added here that when the movement had been 
stopped for several hours, the sections lying in ether-water all 
the while, it began again a few minutes after removal to fresh 
water.) In cells with the movement thus inhibited, more of 
the chlorophyll was made to fall into the lower end of the 
cell, but displacement was much less complete than was 
expected. 
From this experiment it seems that there are other factors 
more potent in preventing a displacement of the cell-contents 
than the movement of the cytoplasm. 
Chara and Nitella. 
Chara and Nitella lend themselves much less readily to 
these experiments than the other plants investigated. As 
a rule the centrifugal force necessary to displace the chloro- 
plasts which lie in the stationary part of the cytoplasm proved 
fatal. The cells are either killed outright, or retain their 
vitality for a short time only. 
In order to bring about a complete displacement in certain 
cells only, it was necessary to continue the centrifugal action 
for five or six hours. It made no difference whether the rota- 
tion of the cytoplasm was first inhibited by ether or not. In 
Chara the results were different in different parts of the plant. 
In the uncorticated cells near the ends of the so-called leaves, 
displacement of the chlorophyll was effected in different 
degrees. (Only terminal portions of good thrifty shoots about 
one centimetre and a half long were used.) Frequently much 
was removed from a tolerably broad strip on both sides of 
the neutral zone ; then again this thinning out of the chloro- 
