PREFACE. 
V 
wished. To explain those principles ; to adduce the 
evidence by which their truth is supposed to be 
proved, or the reasoning upon which they are based 
in cases where direct proof is unattainable ; to show 
the causes of errors now exploded, the insufficiency 
of the arguments by which doubtful theories are still 
defended, and, in fine, to draw a line between what 
is certain and what is doubtful, are some of the ob- 
jects of this publication, which is intended for the 
use of those who, without being willing to occupy 
themselves with a detailed examination of the vast 
mass of evidence upon which the modern science of 
botany is founded, are, nevertheless, anxious to ac- 
quire a distinct idea of the nature of that evidence. 
Another and not less important purpose has been to 
demonstrate, by a series of well-connected proofs, 
that in no department of natural history are the sim- 
plicity and harmony that pervade the universe more 
strikingly manifest than in the vegetable kingdom, 
where the most varied forms are produced by the 
combination of a very small number of distinct organs, 
and the most important phenomena are distinctly ex- 
plained by a few simple laws of life and structure. 
In the execution of these objects, I have followed 
very nearly the method recommended by the cele- 
brated Professor De Candolle, than whom no man is 
entitled to more deference, whether you consider the 
soundness of his judgment in all that relates to order 
and atrangement, or the great experience which a 
long and most successful career of public instruction 
has necessarily given him. 
I have begun with what is called Organography 
(Book I.) ; or an explanation of the exact structure 
of plants ; a branch of the subject comprehending 
what relates either to the various forms of tissue of 
