PLANT RESPONSE 945 
Plant Response as a Means of Physiological Investigation. By Jacapis 
HUNDER Bose. Pp. xxxviii, and 781; figs. 278. Longmans, 
Is. 
Pror. Boss is well known for his book, Response in the Living and 
Non-Living, noticed in this Journal for 1903, p. 28, in which he 
or by chemical and electrical stimuli—show a fundamental unity. 
They are but different exprossione of one response, that of con- 
traction of the protoplasm leading to a “ negative turgidity varia- 
tion,” and often to an actual contraction of the tissues. It is this 
contraction of the protoplasm which causes the well-known excre- 
tion of water from the cut petiole of Mimosa; but Prof. Bose con- 
tends that this reaction is common to plants, i.e. there is no 
e author further extends this view of the contraction of 
protoplasm under ——— to explain not only ‘eartslt and 
heliotropic curvatures, but also such phenomena as water-ascen 
and ordinary gro seer processes. The effect of unilateral stem- 
relation by gravity and light, and the consequent protoplasmic con- 
traction, is to retard rc on one side, and thus ae Be men 
f. Bose describes so ee: a number of new experiments, and 
his views themselves are so novel, that judgment can only be 
