CONTENTS 



CHAPTER I 

 INTRODUCTION 



PAGES 



Permanent high production The relation of physiology to pro- 

 duction Physiology and ecology Physiological processes 

 Environment Crop ecology Literature of Plant Physi- 

 ology Physiology and other sciences References . 1-14 



The cell a physiological unit Early use of the term "cell" Meri- 

 stem or embryonic cells Cytoplasm The nucleus Plas- 

 tids The cell- wall Cell-sap Cell-forms Parenchyma 

 Sclerenchyma Tracheae or vessels Sieve tubes Proto- 

 plasmic movement Protoplasmic irritability and response 

 Laboratory work References 15-34 



CHAPTER III 



THE WATER-CONTENT OF PLANTS AND THE GENERAL RELATIONS 

 OF ROOT SYSTEMS 



Hydrostatic rigidity The water-content of plants Variation 

 in water-content of organs The water-absorbing system 

 The root habit of crops The production of root-hairs 

 Root-hairs and the water-content of the soil The root-cap 

 Structure of the root-tip Soil particles Soil texture 



ix 



