CONTENTS 



CHAPTER I 



PLANT SCRIPTS 



PAGE 



Action of environment on plant — Revelation of internal condition 

 by character of response — Problems to be solved — Electrical 

 response — Mechanical response — Motile organ in Mimosa 

 pudica — Response in plant and animal — Different phases 

 of the responsive movement — Graphic record — Determination 

 of absolute movement of leaf and its time-relations — 

 Characteristic effects of different agencies on the response- 

 curve — Specific difficulties in recording plant-response . i 



CHAPTER II 



THE RESONANT RECORDER 



Advantages of intermittent contact in record — Two types of 

 apparatus : the Oscillating Recorder, and the Resonant 

 Recorder — Coercer and Vibrator — Perfect tuning — Recorders 

 with standardised frequencies — Slide and clockwork — The 

 record its own chronogram — Smoked surface and its fixation — 

 Adjustments of the writer — Records with continuous and 

 intermittent contacts ....... 1 1 



CHAPTER III 



METHODS OF STIMULATION 



Different methods of stimulating the plant : mechanical, chemical, 

 thermal and electrical — Difficulties of securing quantitative 

 stimuli — Direct and indirect stimulation — Ideal modes of 

 stimulation — Electro-thermic stimulation — Stimulation by 

 constant current — Stimulation by condenser-discharge — Non- 

 polarisable electrodes — Direct, extra-electrodal, and intra- 

 electrodal stimulation — Stimulation by induction-shock — 

 Effects of make- and break-shock — Excitation by tetanising 

 shock .......... 23 



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