CONTENTS 



PAGE 



INTRODUCTION I 



CHAPTER 



I. LIVING AND LIFELESS MATTER 6 



1. The Chemical Composition 7 



2. Metabolism or the Power of Waste and Repair .... 9 



3. Growth by Intussusception 12 



4. Reproduction ....... 13 



5. Power of Adaptation . 15 



II. PROTOPLASM AND THE CELL, AND ORGANISMS OF ONE CELL ... 26 



A. The Organization and Vitality of Yeast Cells 29 



B. Bacteria 34 



C. Enzymes, Hormones and Vitamines . . . 37 



III. ORGANISMS OF ONE CELL, Continued. . . . . . . .. . . . . 44 



A. Amoeba proteus ' . . . 44 



B. Flagellated Protozoa, Chilomonas and Allied Forms . . 53 



C. A Ciliated Protozoon, Paramecium caudatum 60 



D. Biological Problems associated with Protozoa .... 65 



IV. ORGANISMS OF TISSUES 76 



A. Hydra fusca and Hydra viridis 82 



Histology ...,",:,'... 83 



Physiology 90 



Symbiosis 96 



Polymorphism 98 



B. Summary 100 



V. PLANTS, THE FOOD OF ANIMALS AND THE SOURCES OF ANIMAL 



ENERGY . . . . 103 



A. The Food of Animals 103 



B. Pleurococcus pluviatilis and Sphaerella lacustris. . . . 106 



C. Pteridium aquilinum no 



Histology * 112 



General physiology 1 1 8 



Reproduction 122 



VI. ORGANS AND ORGAN SYSTEMS 13 



I. General.-. . . . 130 



II. Structures and Functions of the Earthworm, Lumbri- 



cus sp .'.'. J3 1 



A. Habits and Mode of Life 132 



B. Regional Differentiation 133 



, C. Internal Structure , . 136 



vii 



