II4 BOTANICAL GAZETTE [SEPTEMBER 
protoplasmic streaming was inhibited. After a time the flow was 
resumed. No disorganization of the cells occurred. 
JURGENSEN (12) worked with Vallisneria,. noting the effect of 
the direct current on protoplasmic rotation. He placed sections of 
leaves on a special object holder, in distilled water, with copper 
electrodes in contact with the ends of the section. The effect was 
observed with a microscope giving a magnification of 235-680 
diameters. Using 2-4 Grove cells, the speed of rotation of proto- 
plasm was decreased, and long continued exposure to such weak 
currents brought about an inhibition of the streaming. If the 
current was discontinued after slowing down the rotation, but 
before it had entirely stopped, the original speed of rotation was 
reacquired after a time. When rotation had completely stopped, 
even though the current was broken immediately, movement was 
never resumed. Stronger currents produced the same effect as the 
weaker currents in much less time, the current from 30 cells sufficing 
to produce immediate and permanent inhibition of rotation. If the 
current was continued, the protoplasm contracted and gradually 
_ migrated toward the end of the cell nearest the anode, where it 
formed a dense mass against the wall. At break of current this 
mass would rebound toward the opposite end of the cell. On 
reversing the direction of current the mass migrated toward the 
opposite end of the cell, that is, toward the now positive end. 
JURGENSEN regarded these phenomena as coordinate with results 
he had previously obtained with unorganized bodies. 
Du Bots-REymonp (7) had previously published similar results, 
experimenting with starch grains in the cells of a section of living 
potato tuber. Movement toward the anode was observed, and, as 
in Vallisneria cells, a reversal of current brought the starch grains 
to the opposite wall. 
KUHNE (14), using the direct current on a plasmodium of a 
myxomycete, grown on the slide between platinum electrodes 4 
mm. apart, reported nuclei moving toward the anode, the cytoplasm 
toward the cathode. In the cells of Tradescantia stamen hairs the 
entire cell contents moved toward the anode. The ends of the cells 
toward the cathode changed from their characteristic purple to 
- green, and the opposite end changed to a light red color. KtHNE 
