CONTENTS 



CHAPTER PAGE 



FOREWORD TO TEACHERS . .7 



I. SOME REASONS FOR THE STUDY oy Bioi.ocv 15 



II. THE ENVIRONMENT OF PLANTS AND ANIMALS . 19 



III. THE INTERRELATIONS oy PLANTS AND ANIMALS 



IV. THE FUNCTIONS AND COMPOSITION oy LIVING THINGS . 47 

 V. PLANT GROWTH AND NUTRITION - -THE CAUSES oy GROWTH 58 



VI. THE ORGANS oy NUTRITION IN PLANTS- THE SOIL AND 



ITS RELATION TO ROOTS 71 



VII. PLANT GROWTH AND NUTRITION -- PLANTS MAKE FOOD . 84 

 VIII. PLANT GROWTH AND NUTRITION- -THE CIRCULATION AND 



FINAL USES oy FOOD BY PLANTS . . . .97 

 IX. OUR FORESTS, THEIR USES AND THE NECESSITY oy THEIR 



PROTECTION . 105 



X. THE ECONOMIC RELATION oy GREEN PLANTS TO MAN . 117 

 XL PLANTS WITHOUT CHLOROPHYLL IN THEIR RELATION TO 



MAN ....... . 1 : >0 



XII. THE RELATIONS oy PLANTS TO ANIMALS . . 159 



XIII. SINGLE-CELLED ANIMALS CONSIDERED AS ORGANISMS . 166 



XIV. DIVISION oy LABOR, THE VARIOUS FORMS oy PLANTS AND 



ANIMALS ..... 173 



XV. THE ECONOMIC IMPORTANCE oy ANIMALS . .197 



XVI. AN INTRODUCTORY STUDY oy VERTEBRATES 



XVII. HEREDITY, VARIATION, PLANT AND ANIMAL BREEDING . 249 



XVIII. THE HUMAN MACHINE AND ITS NEEDS . 266 



XIX. FOODS AND DIETARIES . . 272 



XX. DIGESTION AND ABSORPTION . 296 



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