Vv'OODS 



MO' F 



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CONTENTS X > . ^ r-c- 



Publisher's Note \ P^g^ / 



Pflr^ I— LIGHT AND VEGETATION 



Introduction 1 1 



I Light and Thermal Radiations 17 



II Solar Radiation 34 



III Photometry of the Leaf 47 



IV The Role of Infra-red Radiation 60 



V The Role of Ultra-violet Radiation 69 



VI The Role of Visible Light 77 



VII Photosynthesis 88 



VIII Theories of Assimilation 102 



IX Photosynthesis and Photography 124 



X Phototropism 133 



XI Photoperiodism 137 

 Conclusions 146 



Part II— CHLOROPHYLL AND ENERGY 



Introduction 149 



I Historical 151 



II Chlorophyll 160 



III The Chemistry of Photosynthesis 172 



IV Assimilation 194 



V Chlorophyll and Ourselves 209 

 Short Bibliography 225 

 Index 227 



5 



'^^139 



