PA Rtn, EE. 
PRINCIPLES OF CLASSIFICATION AND 
SYSTEMATIC BOTANY, 
INTRODUCTION. 
WHENEVER, in the pursuit of knowledge, we come in contact 
with a large number of isolated facts, we almost always try, 
whether consciously or not, to arrange these facts in some sort 
of order. We usually try to group them together or place 
them in some sort of sequence, and the more completely and 
perfectly we succeed in placing them so that their natural rela- 
tionships are brought out, the more complete and perfect is our 
classification. This is true of all kinds of knowledge and of all 
classes of facts. 
Hitherto in dealing with plants we have treated them as if 
they were all isolated and distinct from one another, or if, by 
the order we have followed, a kind of relationship has been 
pointed out, this has only been done in an indirect manner. 
A large number of facts concerning them has been accumu- 
lated, and if we are to make further progress we must try and 
arrange these facts, and see whether we cannot get some order 
out of them. 
In trying to classify plants, or, indeed, any other group of 
organized structures, we may proceed on one of two methods. 
We may choose to construct a scheme of classification in 
which special prominence is given to any one set of characters 
alone, all others being treated as more or less subservient. This 
was the mode in which the old botanists went to work; but 
their schemes of classification necessarily always proved so 
unsatisfactory that new ones were constantly being brought 
forward. This method culminated in the scheme proposed by 
