xviii INTRODUCTION. 



part of this extensive science that may be more success- 

 fully pursued by ordinary school methods of instruction. 

 This is physiological botany. By means of diagrams and 

 the explanations of the text, the scholar is enabled to per- 

 ceive how and of what the parts of plants are built up, 

 and what functions these parts perform in its history as a 

 living being. A valuable manual on this branch of botany 

 by an eminent authority will shortly appear in this series, 

 which will complete the exposition of the science here 

 begun. 



