Page:Life Movements in Plants.djvu/233

Rh This caused a depression of growth rate to 0'04 ,u per

second. A transverse cut, I ﬁnd, gives rise to a more. intense stimulation, than a longitudinal slit.

TABLE Xth.——-t'}t“b‘l*ll‘l‘ 0|? MECII.\‘II(3;\L llttilttAt‘lth .\.\ll\ Ht“ WOUND 0N thOW't‘lt.

(Zap/lynch lites.)

tNaturo of stimulus. (‘onditiou. Rate of growth. ' l i t j Mechanical t'ric- Normal rato 0'18 ’1. per sec. ‘ i tion.

Immediately after sti—

mulation ‘11 ,1, ,,

i 15 minutes after sti- t mutation (l'l-l p. ,,
 * tit) minutos after sti—

l mutation 0'18 in ,, I l m. — “I
 * Prick with needle Normal rate 0'18 ,1. per soc.

! mutation 0'05 ,1, ,, 3 15 minutes after sti- t mutation 0'07 ,1. ,, i l tit) minutes after sti- i I mutation 0'12 ,u ,,
 * lmnu-diatety after st i-

The effect of mechanical stimulus on growth is thus similar to that induced by electrical stimulus. Mode-ate stimulus of rough contact induces an incipient contraction, seen in retardation of growth, the recovery being complete in the course of an hour; but intense stimulation, induCed