PRINCIPLES 



OF 



SCIENTIFIC BOTANY. 



INTRODUCTION. 



Botany comprehends the knowledge of Plants. These, 

 like all other natural bodies, may be considered under a two- 

 fold aspect ; either in relation to their external properties, or 

 with a view to their internal structure, their nature, and the 

 causes of the phenomena which they present. 



2. 



Botany, accordingly, divides itself into two principal de- 

 partments, which, in our days, can no longer be separated, 

 since they mutually support and illustrate each other. 



1. The Natural History of' Plants^ which has been exclu- 

 sively denominated Botany. This comprehends the know- 

 ledge of the external marks of plants, and the means of dis- 

 tinguishing them; their Description, Determination, and 

 Classification. This department includes three subdivisions. 



1 , The Nomenclature^ {Glossologie De Candolle, falsely 

 called Terminology). Under this subdivision, we include the 

 knowledge of the expressions, by which the different organs, 



