Centrifugal Force upon the Cell, 345 
more susceptible to injury than those of the other plants. 
Many seemed to have been killed outright while others died 
soon after centrifugal action. 
Funaria. 
Small, fresh specimens of Funaria were fastened upon 
a slide in the usual way. Individual leaves to be observed in 
detail after centrifugal action were then carefully removed 
from the plant and mounted in water. When such leaves 
were returned to the moist chamber to be kept for subsequent 
observation, the cover-glass was removed to allow free access 
of air. The behaviour of the cell-contents in leaves that had 
been removed from the plant was about the same as in those 
which were not detached. 
The character of displacement varied in different parts of 
the leaf. In the longer and larger cells near the base, dis- 
placement was more easily brought about than in the smaller 
isodiametric ones of the terminal third or fourth of the leaf. 
Sometimes the contents in basal cells experienced a total 
displacement, while in those at the apex of the same leaf 
no perceptible change in the position of chloroplast or any 
other inclusion could be detected. Such leaves then presented 
a complete transition from cells in which all the contents 
capable of being displaced were made to fall into the lower 
end of the cell, to those in which no change in the position of 
any chloroplast was apparent. 
The reason for this is unknown to the writer, unless it 
be due to the density or firmness of that part of the primordial 
utricle in which the chloroplasts are imbedded. According 
to all appearances the chloroplasts were about the same size 
with the same quantity of starch enclosed in each. If their 
specific gravity be less than that of those in the basal cells, 
no method of settling the question suggested itself at the 
time. 
An average cell with displaced contents is shown in 
Fig. 10. It appears that the contents fill about one-half 
A a 3 
