326 Mot tier . — The Effect of 
Dehnecke states also that, when the plant is revolved 
slowly in a horizontal position upon the klinostat, the starch- 
grains will fall from one edge of the cell to the other, and may 
thus be made to glide round within the cell in a plane parallel 
to the transverse axis. 
It is evident, a priori , that the heavier inclusions of the 
protoplasm may be made to fall toward any side of the cell 
by means of centrifugal force. It was the purpose of the 
writer to determine, at least in a general way, what parts of 
the living substance and its inclusions could be displaced 
within the cell by means of a centrifugal force several hundred- 
fold greater than that of gravity acting for certain definite but 
usually short periods of time, and to see what effect such 
displacement might have upon the individual cell. 
The results in many cases were surprising, and may prove 
to be of considerable theoretical importance, so that a some- 
what detailed discussion will, no doubt, be of interest to the 
botanist, and especially to the experimental cytologist, whether 
his object of investigation be the plant or animal cell. 
Various Algae, leaves of Mosses, of Elodea and Vallisneria , 
together with trichomes and seedlings of several Phanerogams, 
furnished material for investigation. Of the Algae those most 
easily procurable at the time were selected, such as Cladophora , 
Spirogyra , Oedogonium , V aucheria, Mesocarpus , Char a and 
Nitella. Trichomes of Urtica, Momordica , Cucurbit a , Primula , 
with many others ; stamen-hairs of Tradescantia , leaves of 
Funaria and Elodea, and sections from leaves of Vallisneria , 
together with seedlings of Zea Mays , Vicia Faba , Ricinus , 
Phaseolus , & c., were also found suitable for experimentation. 
A centrifugal force varying from 1700 to 1930 times that of 
gravity was generated by the use of an ordinary milk-centrifuge 
driven by a gas-motor. 
The objects selected for study were placed in strong glass 
cylinders, which were securely packed in the drum of the 
centrifugal machine. The drum permitted of a slight varia- 
tion in the length of the radius, so that by moving the 
cylinders toward or from the centre a considerable difference 
