CONTENTS, 
Xl 
BOOK III. 
PHYSIOLOGY. 
CHAPTER L 
Molecular Forces in the Plant. 
PAGE 
Sect. I. The Condition of Aggregation of Organised Structures . . . .663 
„ 2. Movement of Water in Plants . . 674 
3. Movements of Gases in Plants 691 
CHAPTER II. 
Chemical Processes in the Plant. 
Sect. 4. The Elementary Constituents of the Food of Plants 694 
„ 5. Assimilation and Metastasis 703 
„ 6. The Respiration of Plants 721 
CHAPTER III. 
General Conditions of Plant-life. 
Sect. 7. The Influence of Temperature on Vegetation 725 
„ 8. Action of Light on Vegetation 737 
„ 9. Electricity 768 
„ 10. Action of Gravitation on the Processes of Vegetation 770 
CHAPTER IV. 
The Mechanics of Growth. 
Sect. II. Definition 773 
„ 12. Various Causes of Growth . . 775 
„ 13. General Properties of the Growing Parts of Plants 778 
5, 14. Causes of the Condition of Tension in Plants 787 
„ 15. Phenomena due to the Tension of Tissues in the Growing Parts of Plants . 794 
„ 16. Modification of Growth caused by Pressure and Traction .... 809 
„ 17. Course of the Growth in Length under constant External Conditions . .815 
„ 18. Periodicity of Growth in Length caused by the alternation of Day and 
Night 823 
„ 19. Effect of Temperature on Growth 828 
„ 20. Action of Light on Growth in Length. — Heliotropism . . . .832 
„ 21. Action of Gravitation on Growth in Length. — Geotropism . . . . 839 
„ 22. Unequal Growth ............ 854 
