CONTENTS XllI 



PAGE 



Water. — ^Path of Water Ascent. — Influence of Environ- 

 ment on the Water Conducting Tissues. — Illustrative 

 Studies . . . IOI-I22 



CHAPTER VIII 



Intake and Distribution or Gases 



Oxygen and Carbon Dioxide Necessary to Plants. — The 

 Stomata. — The Relation of Stomata to the Environ- 

 ment. — The Lenticels. — The Intercellular Spaces. — 

 Diosmosis of Gases into and from Living Cells. — Motive 

 Power in the Distribution of Gases throughout Plants. — 

 Illustrative Studies . . . . .... . 123-137 



CHAPTER IX 



Construction of the Plant's Food 



The Source and Uses of Food. — Food Building Apparatus. — 

 The Chloroplasts. — ^The Sun's Energy. — The Palisade 

 Cell the Chief Photosynthetic Unit. — Relation of Leaf 

 as a Whole to Photosynthesis. — Conditions Affecting 

 Photosynthesis. — ^Photosynthesis in the Lower Plants. — 

 Synthesis of Food without Light. — Illustrative Studies . 138-156 



CHAPTER X 



Transport oe Foods throughout the Plants 



Need of Circulatory Tissues. — Evidence that the Phloem 

 Carries the Food. — Evidence that the Tracheal Tissues 

 Assist the Phloem in the Upward Transmission of Food. 

 — Relation of Phloem Elements to Other Tissues. — 

 The Course of Food Distribution. — ^Annual Additions 

 to the Food-conducting Tissues. — Relation of One 

 Year's Phloem Elements to those of the Next. — 

 Character of Food while in Transport. — The Pro- 

 pelling Power in Food Transport. — Illustrative Studies. 157—174 



