xiv CONTENTS. 



PAGE 



CHAPTER V. 



ACTION OF lEATES. 



Their Nature, Structure, Veiiis, Epidermis, Stomatea. — Effect of Light. — 

 Digestion or decompositiou of Carbonic Acid. — Insensible Perspiration. 

 Formation of Secretions. — ^Fall of the Lea£ — Formation of Buds by 

 Leaves 54 



CHAPTER VI. 



ACTION OF PIOWEES. 



Structure of Flowers. — Names of their Parts. — Tendency of the Parts to 

 alter and change into each other, and into Leaves. — Double Flowers.^ 

 Analogy of Flowers to Branches. — Cause of the Production of Flowers. 

 Of Productiveness. — Of Sterility. — Uses of the Parts of a Flower. — 

 Fertilisation. — Hybrids.— Crossbreds ....... 81 



CHAPTER VII. 



OF THE MATTTEATION OF THE FETJIT. 



Changes it undergoes. — Is fed by Branches upon Organisable Matter fur- 

 nished by Leaves. — ^Physiological use of the Fruit. — Nature of Secre- 

 tions. — The changes they undergo. — Effect of Heat — of Sunlight — of 

 Water. — Seeds. — Source of their Food. — Cause of their Longevity — of 

 their Destruction. — ^Difference in their Vigour 97 



CHAPTER VIII, 



OF TEMPBEATUEE. 



Limits of Temperature endurable by Plants. — Effects of a too high Tempe- 

 rature — of a too low Temperature. — Frost. — Alternations of Tempera- 

 ture. — Day and Night. — ^Winter and Summer. — Temperature of Earth 

 and Atmosphere 106 



BOOK II. 



OP THE PHYSIOLOGICAL PRINCIPLES UPON WHICH THE OPERATIONS OF 



HORTICULTURE ESSENTIALLY DEPEND I33 



CHAPTER I. 

 Of Bottom Heat • j3^ 



CHAPTER II. 

 Of the Moisture of the Soil. — Watering jgg 



