XXVIU CONTENTS. 



Page 



2. Functions of Prosenchyma 726 



3. FunctioRS of Vessels 727 



Functions of the Laticiferous Vessels . . . 728 



4. Functions of the Epidermal Tissue and its Appendages 728 



Hairs and Glands 729 



5. Functions of the Intercellular System .... 730 



Section 2. 



physiology op the organs of nutrition or vege- 

 TATION 730 



1. Of the Eoot or Descending Axis .... 730 



Absorption by the Root . • 730 



Excretion of Roots ^ . 732 



2. Of the Stem or Ascending Axis 733 



Special Functions of the difierent Parts of the Stem 733 



1. The Pith 733 



2. The Wood 733 



3. The :Medullary Rays 734 



4. The Bark 734 



3 Of the Leaves 734 



1. Exhalation of Watery Vapour by Leaves . .734 



2. Absorption of Fluids by Leaves .... 737 



3. Absorption and Exhalation of Gases by Leaves . 737 



Respiration and Assimilation .... 739 



4. Formation of the Products and Secretions by 



Leaves 741 



5. Effects of Gases generally upon Leaves . . 742 



Wardian Cases 743 



6. Colour of Leaves 744 



7. Defohation, or the Fall of the Leaf . . .745 



8. Development of Leaves 746 



Section 3. 



physiology of the organs of reproduction 



Functions of Bracts and Floral Envelopes 

 Of tlie Essential Organs of Reproduction 

 Sexuality of Plants .... 

 Sexual Rci)roduction of Plants 



1. Reproduction of Cryptogamous or Acotyledo 

 nous Plants 

 A. Reproduction of Thallogens 

 Fungi and Lichens 

 OfAlgai . 



1 . Of Conjugation . 



2. Impregnation by ciliated sperma 



tozoids 



746 



746 



748 

 748 

 748 



749 

 749 

 749 

 749 

 749 



750 



