CONTENTS. 



Preface and Introduction .... Page 1 



FIRST LECTURE. 



The Eye and the Microscope . . .13 



SECOND LECTURE. 



On the Internal Structure of Plants . . .39 



THIRD LECTURE. 

 On the Propagation of Plants . . .57 



FOURTH LECTURE. 



The Morphology of Plants . . .77 



FIFTH LECTURE. 



About the Weather . . . .105 



SIXTH LECTURE. 



What does Man live upon ? (First Reply) . . 1 29 



SEVENTH LECTURE. 

 What does Man live upon ? (Second Reply) . .155 



