CONTENTS 



LECTURE V 



THE ROLE OF ELECTROLYTES IN THE FORMATION AND PRESERVATION OF 



LIVING MATTER 



PAGE 



1. On the Specific Difference between the Nutritive Solutions for Plants and Animals 



Protective Solutions and Nutrient Solutions . . . . . .71 



2. Concerning a Theory of Irritability and the Role of Na, K, and Ca for Animal Life 



Rhythmical Contractions in Skeletal Muscle, in Medusa?, and the Ven- 

 tricle of the Heart Contact Irritability in Muscle Analogies to the Role 

 of Salts in Coagulation of Milk Significance for the Understanding of 

 Functional Nervous Diseases The Action of Purgatives .... 78 



3. The Reaction of Living Matter and the Role of Bicarbonates in the Preservation 



of Life -95 



4. Electrical Stimulation . 9& 



LECTURE VI 

 THE EFFECTS OF HEAT AND RADIANT ENERGY UPON LIVING MATTER 



I. Effects of Heat Upper Temperature Limit of Life Influence of Reaction- 

 velocity upon Biological Processes Lower Temperature Limit Other 

 Biological Effects of Heat 106 



?.. General Effects of Radiant Energy upon Living Matter Chemical Action of Light 



upon Organisms . . . . . . . . . . .112 



LECTURE VII 

 HELIOTROPISM 



1. The Heliotropism of Sessile Organisms 117 



2. Heliotropism of Free-moving Animals . . . . . . . . .124 



3. The Control of the Precision and Sense of Heliotropic Reactions in Animals . . 130 



4. The Reaction of Animals to Sudden Changes in the Intensity of Light . . 135 



LECTURE VIII 



FURTHER FACTS CONCERNING TROPISMS AND RELATED PHENOMENA 



1. General Theory of Tropisms ... 138 



2. Galvanotropism ......... I 4 l 



3. Geotropism r 47 



4. Chemotropism and Related Phenomena *5 2 



5. Stereotropism J 55 



6. Concluding Remarks concerning Tropismlike Reactions 158 



LECTURE IX 



FERTILIZATION 



1. The Specific Character of the Fertilizing Power of the Spermatozoon Hybrid 



Fertilization . . . . 161 



2. Artificial Parthenogenesis and the Theory of Fertilization . . . 164 



