CONTENTS. 



PAGE. 



1. Growth and colloidal reactions 1 



II. Fundamental features of phytocolloids 11 



III. The constituents of biocolloids which affect hydration and growth 27 



IV. The effect of salts and acids on biocolloids and cell-masses 37 



V. The effects of organic acids and their amino compounds on hydration and 



growth 54 



VI. Reactions of biocolloids and cell-masses to culture solutions, bog, swamp, and 



ground water, and other solutions 65 



Vll. Fluctuating or alternating hydration effects. Basis of xerophily and succu- 

 lence 78 



V11I. Water deficit, or unsatisfied hydration capacity 92 



IX. Temperature and the bydration and growth of colloids and of cell-masses. ... 110 



X. Imbibition and growth of Opuntia 128 



XI. The hydration reactions and growth of Mesembryanthemum, Helianthus, and 



Phaseolus 145 



XII. Water-content, dry weight, and other general considerations 161 



Literature cited 174 



VI 



