Vi CONTENTS 



CHAPTER PAGE 



XIX. LIFE IN WATER . . . . . 197 



XX. RURAL SCHOOL GARDENING .... 203 

 XXI. SUGGESTIONS FOR CONDUCTING WORK IN 



THE SEVENTH AND EIGHTH GRADES . 207 

 XXII. POLLINATION AND SEED FORMING . .210 



XXIII. PLANT BREEDING 214 



XXIV. INSECTS 217 



XXV. FUNGI AND BACTERIA 224 



XXVI. SELECTING, JUDGING, AND STORING SEED 



CORN 231 



XXVII. PHYSICAL EXPERIMENTS 235 



XXVIII. SOME EFFECTS OF HEAT ON BODIES . . 241 



XXIX. METHODS OF HEATING BODIES . . . 244 



XXX. GERMINATION OF SEEDS 249 



XXXI. STUDY OF OATS 255 



XXXII. PLANT PRODUCTS . . . . . . 259 



XXXIII. SIMPLE EXPERIMENTS IN SOIL CHEMISTRY . 264 

 XXXIV. SOIL AND ITS ORIGIN . . . . .277 



XXXV. SOME PHYSICAL PROPERTIES AND CONDI- 

 TIONS OF SOIL . 280 



XXXVI. How PLANTS Do THEIR WORK ... 288 

 XXXVII. How TO KEEP THE SOIL IN CONDITION TO 



SUPPLY THE NEEDS OF PLANTS . .299 



PART FOUR 



XXXVIIL BIRD STUDY 303 



XXXIX. SCHOOL GARDENS 314 



XL. SOME FUNDAMENTAL MISCONCEPTIONS . . 320 



XLI. THE GENERAL LIFE PROCESSES . . . 324 



XLII. EXPLANATIONS OF EVOLUTION . . . 333 



XLIII. EVOLUTION AS SHOWN BY PLANTS . . 339 



INDEX 351 



