CONTENTS
ix
page
current—Effect of electric waves—Effect of statical electric induction—Effect of thermal rays—Effect of light—Effect of red and of blue light—Effect of carbonic acid gas—Effect of ether—Effect of chloroform—Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
98 | |
CHAPTER VIII
THE DIURNAL VARIATION OF TRANSPIRATION
Diurnal variation of transpiration in plants with roots—Diurnal variation after removal of the root—The Radiograph— Diurnal variation of temperature and of light—Balancing evaporation against transpiration—The Differential Balance—The optimum temperature for transpiration—Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
117 | |
CHAPTER IX
EXUDATION BY THE ROOT-STOCK
The Recorder of Exudation—The Tilter and the Electromagnetic Writer—Composition of exuded sap—Continuous record of exudation—Effect of drought—Effect of mechanical and electrical stimulus—Effect of poison—Effect of anæsthetics—Continuity of action in root and in shoot—Activity of terminal layer at the cut end—Expulsion of sap by living cells—Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
131 | |
CHAPTER X
THE RELATION BETWEEN ROOT-PRESSURE AND EXUDATION
General considerations—Diurnal periodicity of root-pressure—The recording apparatus—Relation between temperature and
pressure—Diurnal variation of pressure in deciduous trees—Diurnal variation of exudation—The effect of light—Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
146 | |
CHAPTER XI
DIURNAL VARIATION OF PRESSURE AND EXUDATION IN PLANTS WITH LEAVES
Complexity arising from fluctuating factors of absorption and excretion—Hydraulic and electric model—Diurnal variation of pressure in root stock—Effect of light—Explanation of irregular variation of pressure in trees—Diurnal variation of exudation in root stock—Positive and negative exudation—Exudation in Pithecolobium—Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
160 | |
