CONTENTS 



CONVERSATION I 



INTRODUCTION. 



Distinction between Minerals and Organised Beings. Distinction be- 

 tween the Animal and Vegetable Kingdoms. Effect of Vegetable Poi- 

 sons on Plants. Irritability and Contractibility of Plants. Properties 

 of Plants, relative to Structure and to Vitality. Organs of Plants of 

 four kinds: 1. Cellular System ; 2. Vascular System ; 3. Tracheae; 4. 

 Strangulated Vessels. Fibres of Plants. Layers of Wood. Cuti- 

 cle. " Page 13. 



CONVERSATION II. 



ON ROOTS. 



Six Periods relative to the Nutrition of Plants: 1. Absorption by the 

 Roots; they also fix the Plant in the Ground. Spongioles; suck up 

 whatever is sufficiently minute to enter their Pores. Fibrous Roots. 

 Creeping Root. Spindle-shaped, Tap or Pivot Root. Abrupt 

 Root. Bulbous Root. Tuberous or Knotted Root. - 26 



CONVERSATION III. 



ON STEMS. 



Subterranean Stems. Willow Grass. Neck of a Plant. Endogenous 

 Plants, or Monocotyledons. Exogenous Plants, or Dicotyledons. 

 Acotyledons. Structure and growth of Endogenous Stems. Ditto of 

 Exogenous Stems. Wood. Pith. Medullary Rays of Cellular 

 Tissue. Perfect Wood. Alburnum, or New Wood. Bark. Rise 

 of Sap ,- -36 



