X TABLE OF CONTENTS. 



CHAPTER IX. 



PAGE 



How PLANTS OBTAIN THEIR FOOD, 1 81 



1. Sources of Plant Food 81 



2. Parasites and Saprophytes 83 



3. How Fungi Obtain their Food 86 



4. Mycorhiza. 91 



5. Nitrogen-gatherers 92 



6. Lichens 93 



CHAPTER X. 



How PLANTS OBTAIN THEIR FOOD, II 97 



Seedlings, 97. Digestion, 107. Assimilation 109 



CHAPTER XI. 

 RESPIRATION. . . no 



CHAPTER XII. 

 GROWTH 118 



CHAPTER XIII. 

 IRRITABILITY 125 



PART II. MORPHOLOGY AND LIFE HISTORY 

 OF REPRESENTATIVE PLANTS. 



CHAPTER XIV. 

 SPIROGYRA. 136 



CHAPTER XV. 

 VAUCHERIA. > 142 



CHAPTER XVI. 



CEDOGONIUM. 147 



CHAPTER XVH. 



COLEOCH^TE. 153 



CHAPTER XVIII. 

 CLASSIFICATION AND ADDITIONAL STUDIES OF THE ALG^E. 158 



CHAPTER XIX. 

 FUNGI: MuoOR AND SAPROLEGNIA i?7 



