CONTENTS. IX 



CHAPTER X. 

 The Chemical Constituents of Plants. 



PAGE 



§ 1. The Water in the Plant — Amount of Water in Plants — Water 

 in the Protoplasm — Water in the Cell Walla — Water in the 

 Intercellular Spaces — Equilibrium of the Water in the Plant — 

 Disturbance of Equilibrium — Evaporation of Water — Amount 

 of Evaporation — The Movement of tlie Water in the Plant 

 — g 2." As to Solutions— § 3. Plan', Food— The Most Important 

 Elements — Tlie Compounds Used — How the Food is Obtained 

 — How Transported in the Plant 166 



CHAPTER XI. 

 The Chemical Processes in the Plant. 



§ 1. Assimilation — § 2. Metastasis — Its General Nature — Trans- 

 formation of Starch — Nutrition of Protoplasm — Tlie Storing of 

 Reserve Material — The Use of Reserve Material — The Nutri- 

 tion of Parasites and Saprophytes — The Formation of Alkaloids 

 — Results of Metastasis 178 



CHAPTER XII. 

 The Relations of Plants to External Agents. 



§ 1. Temperature — General Relations — Absorption of Water as Af- 

 fected by Temperature — Evaporation — Assimilation — Metasta- 

 sis — Death Irom too High a Temperature — Death from too 

 Low a Temperature — § 2. Light : General Relations of Light 

 to Assimilation, Light, and Metastasis — § 3. Heliotropism — 

 § 4. Geotropism — § 5. Certain Movements of Plants : General 

 Statement, Spontaneous Movements, Movements Dependent 

 upon External Stimuli, Movements of Nutation, Movements 

 ofTorsion 184 



PART II. SPECIAL ANATOMY AND PHYSIOLOGY. 



CHAPTER XIH. 

 Classification. 



Principles of a Natural Classification — Critical — A Comparison of 

 several Systems, ,,,...,.,..., , ,,,,,,,, 303 



