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 



