CONTENTS. xi 



PAGE 



Lecture XVII.— The Nutritive Materials of Plants 282 



Artificial Nutrition of Plants. — Influence of Iron. — Chlorosis. — Quantitative Selection. 

 — Importance of Silica. — Quantity of Ash in Plants. — Source of Nitrogen. — Source 

 of Carbon. — Action of Light in Assimilation. 



Lecture XVIII. — The Production of the Organic Substance of Plants — Assimila- 

 tion 296 



Evolution of Oxygen. — Chlorophyll the Instrument of Assimilation. — Influence of 

 Light on the Development of Chlorophyll. — Assimilation in the various parts of the 

 Solar Spectrum. — Assimilation not effected by the so-called Chemical Rays. — 

 Dependence on the Length of Waves of Light. — The first visible product of Assimi- 

 lation. 



Lecture XIX. — Origin of Starch in the Chlorophyll, and in the Starch-forming 



Corpuscles, Further Behaviour and Fate of the Chlorophyll .... 309 

 Starch in Chlorophyll. — Energy of Assimilation. — Visible Processes in the Chloro- 

 phyll. — Starch-forming Corpuscles. — Cheinical Processes in Chlorophyll. — Emptying 

 of Leaves in Autumn. — Colouring Matter of Chlorophyll. 



Lecture XX. — Chemical Metamorphoses of the Products of Assimilation. Phy- 

 siological Classification of the Products of Metabolism 323 



Origin of Proteids. — Employment of Reserve-materials. — Biological Significance of 

 products of Metabolism. — Reservoirs of Reserve-materials. — Forms of Reserv^e- 

 materials. — Aleurone-grains and Crystalloids. — Inulin. — Starch-grains. — Granulöse 

 and Cellulose of Starch-grains. 



Lecture XXL— Renewal of Activity of Reserve-Materials. Ferments. Dormant 



Periods 341 



Ferments. — Growing Organs produce Ferments. — Peptones. — Asparagin. — Fats. — 

 Naegeli's distinction between Ferment-action and Fermentation. — Resting Periods 

 of Vegetation. 



Lecture XXII. — Passage of the Plastic-Materials through the Tissues . . . 353 

 Transport of Constructive Materials over large Distances. — Employment of the 

 Constructive Materials in Growing Organs. — Movement and Consumption of the 

 Constructive Materials. — Mechanics of the Movements.— Movement in Latex-tubes. 

 — Movements induced by Growth. 



Lecture XXIII. — The Absorption of Organic Nutritive Materials. Parasites. 



Saprophytes. Insectivorous Plants 366 



Nutrition of Parasites. — Action of Parasites on their Hosts. — Connection of Parasites 

 with their Hosts. — Sources of the Plastic Substances of Parasites. — Comparison with 

 Seedlings. — Diotiaa vmscipida. — Drosera. — Nepenthes and other Insectivorous 

 Plants. 



Lecture XXIV. — Lecture xxiii, continued. — Nutrition of Fungi. Lichens . . 380 

 Various effects of Fungi on their Substratum. — Nutritive Materials of Fungi. — 

 Nutritive and Non-nutritive Organic Substances. — Formation of Fat. — Fennentation 

 of Yeast. — Bacteria. — Putrefaction. — Tree-killing Fungi. — Ferment-action and Fer- 

 mentation of Fungi.— Parasitism of Lichen-fungi. — Configuration of Lichens con- 

 ditioned by Chlorophyll. 



Lecture XXV. — The Respiration of Plants. Spontaneous Evolution of Heat. 



Phosphorescence 395 



Absorption of Oxygen and Evolution of Carbon Dioxide. — Quantity of Carbon 

 Dioxide respired. — Destruction of Organic Substance by Respiration. — Intra- 

 molecular Respiration. — Purpose of Respiration. — Measurement of Spontaneous 

 Heat. — Production of Light by Respiration. 



