viii » CONTENTS 



SEC. PAGE 



8. Why and how ^ould we replace the chief nutritive substance 



in the soil ? 5^ 



(a.) Fallow . . , . . 52 



(b.) Inorganic manures . . . . ,. -53 



(c.) Organic manures . 55 



(d.) Stable manures 5^ 



9. How can the soil best meet the requirements of the roots for 



air ? . . ■ . . . ; . . . . .61 



10. How can we improve our fields so as to obtain the best 



possible crops ? 65 



1 1. How is the nutrition of pot-plants effected 1 .... 70 



12. How do aerial roots nourish a plant ? 75 



13. How do ordinary roots obtain their necessary supply of air ? . 77 



;'. CHAPTER IV 



THE TREATMENT OF ROOTS 



14. How should roots be treated in transplanting ? . . . 81 



(a.) A root system which has been considerably pruned . 81 

 (6.) A root system from which only the delicate roots 



have been removed . , . . . -85 

 (c.) The treatment of roots in re-potting . . . -85 

 (d.) The treatment of roots in transplanting in the open . 87 



CHAPTER V 

 THE STEM 



15. What is the structure of the stem ? . . ... 94 



16. What is cambium ? ... 98 



17. What is the function of the cambium in the ordinary course of 



growth] 103 



18. How does the stem as a whole perform its functions ? . . .105 



CHAPTER VI 

 THE LEAF 



19. Which cells of the leaf are the most essential ? . 



20. How are the assimilating cells of the leaf protected ? . 



21. How are the assimilating cells arranged within the leaf ? 



22. How is the leaf developed ? 



23. What substances does the leaf chiefly form ? 



24. How does the leaf actually perform its assimilatory function ? 



108 

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 118 

 120 

 122 

 127 



