LIST OF ILLUSTRATIONS 



FIGURE PAGE 



1. Protococcus plants 6 



2. Spirogyra filament 6 



3. Apple leaf in section, showing cells ..... 6 



4. Germination of beans, showing need of oxygen ... 19 



5. Germination of rice, showing need of oxygen ... 20 



6. Seed-tester 23 



7. Germinating pumpkin seed ....... 26 



8. Plantlet of pumpkin . ...... .27 



9. Plantlet of Indian corn 27 



10. Plantlet of bean 27 



11. Plantlet of pea . .27 



12. Bean plantlets which have lost their cqtyledons ... 29 



13. Radishes grown from heavy and light seed (Bailey) . . 30 



14. Cross-section of germinating Indian corn grain (Frank) . 32 



15. Cross-section of leaf of beech (Strasburger) . . . .35 



16. Starch in potato cell 36 



17. Section of apple leaf ........ 41 



18. Stomata on leaf of garden beet (Frank and Tschirch) . . 42 



19. Stomata on apple leaf 43 



20. Prosenchyma cells from stem of rye (Frank and Tschirch) . 44 



21. Cross-section of vascular bundle of sunflower (Prantl) . 45 



22. Transverse section of corner of bean stem (Potter) . . 46 



23. Live poplar tree with hollow trunk 48 



24. Healing of wound formed by cutting off a branch ... 49 



25. Callus at base of willow cutting ...... 49 



26. Dwarfing of crop by a spruce hedge . . . . .61 



27. Slips of Tradescantia 60 



28. Roots of wheat plant, showing root-hairs (Frank and 



Tschirch) 64 



29. Turnip seedling, showing root-hairs (Frank and Tschirch) . 65 



30. Root-hair magnified with adhering particles of soil (Sachs) . 65 



