342 
Mot tier . — The Effect of 
action the displaced cytoplasm, including the nucleus, appar- 
ently fills the narrow tapering cavity for about one-half the 
length of the hair, except the small knob-like termination 
which still contains, in many cases at least, a vacuole. 
Although the tapering end seemed quite densely filled with 
cytoplasm and the nucleus was compressed into the form 
of an ellipse, yet a constant movement was kept up in the 
cytoplasm, passing into the point of the hair on one side 
of the nucleus and returning on the other. A rotating stream 
passed through the narrow neck into the knob on one side 
and returned along the other. In the broad basal portion of 
the cell in question, the rotation passed over gradually into 
the so-called streaming or circulating movement. 
Twenty-four hours after centrifugal action, the cytoplasm 
was in a large part normally distributed. The nucleus in 
some cases remained for several days in the displaced position ; 
in others it wandered back into the broad basal part of the 
cell, its usual position. After a week the cells of the hairs in 
question were perfectly healthy, the cytoplasm exhibiting an 
active movement. In a few cases the same trichomes of 
Momordica and Urtica were subjected a second time to centri- 
fugal action, with similar results. 
In many trichomes a much longer duration of the centri- 
fugal action is necessary to displace the living contents as 
described, especially where the primordial utricle is very thin 
and fewer heavy inclusions are present. Primula chinensis 
possesses this sort of trichome. Those operated with were 
taken from the petiole of young leaves. The cells contain 
a few pale and scattered chloroplasts, and a relatively small 
amount of cytoplasm with few of the more conspicuous 
granules. The delicate plasmic strands traverse the cell 
chiefly in a longitudinal direction. After five hours’ exposure 
to a centrifugal force of 1820^, the nucleus, chloroplasts, and 
some of the finely granular cytoplasm, were found accumulated 
in the lower ends of the cells. On the next day all was 
normally distributed. 
Hairs of Cucurbita obtained from seedlings were found to be 
