vi PREFACE 
of Botany separately, but rather to develop them all in their 
most natural relationships; and yet morphology, physiology, 
and ecology have been kept so distinct that the teacher will 
have no difficulty in calling attention to these divisions, if it 
is thought desirable. 
In the first five chapters the structure, function, and rela- 
tionships of the most obvious plant organs are considered. 
The purpose has been to use the most easily observed ma- 
terial to give preliminary training in observation and some 
conception of the activities of plants. 
The following thirteen chapters present an outline of the 
plant kingdom in the simplest possible form to be at all ade- 
quate. In these chapters the morphological point of view 
necessarily dominates, but not to the exclusion of the phys- 
iological and ecological. In this presentation of the great 
groups, which is also an outline of classification, there have 
been included special accounts of forms of economic interest; 
not only because such forms as well as any others may 
illustrate groups, but chiefly because there is a growing con- 
viction that Botany in the schools must relate pupils to their 
common experiences, as well as train them in science. For 
the same general reason the brief chapters on plant-breeding 
and forestry have been introduced. 
The four closing chapters include a very brief account of 
plant associations, the most inclusive view of plants. This 
subject is merely introduced rather than developed. 
It cannot be repeated too often that this book will not 
serve its purpose unless it is used as a supplement to the 
teacher, to the laboratory, and to field-work. Furthermore 
it must be insisted that the sequence of the book need not be 
