PREFACE 



Although students vary widely in their reasons for studying 

 Botany, the fundamental facts or principles of the subject are 

 not thereby altered. One has considerable freedom, however, in 

 the presentation of the subject to adapt the subject matter to 

 special aims of different classes of students, and especially is 

 this true in courses for agricultural students, since much of the 

 work in Agriculture is based upon the principles of Botany. In 

 the choice of material to illustrate principles and in the presen- 

 tation of the applications of principles, there is special oppor- 

 tunity to relate courses in Botany to courses in Agriculture. 



In any elementary course in Botany, regardless of the kind of 

 education the student desires to obtain, the primary aim should 

 be to give the student a notion of the fundamental principles of 

 Botany. This aim should be the guiding one in both recitation 

 and laboratory, determining the trend of discussions in recita- 

 tion, and the nature of the material and procedure in the lab- 

 oratory. The primary aim should be accompanied by a secondary 

 aim to relate the subject to the student's major line of work. 

 When the relation of the subject to major lines of work is obvious, 

 the student is more likely to appreciate the subject and is thereby 

 put in a favorable mood to study the subject. Even for students 

 who take Botany merely as a part of a general education, it in no 

 way detracts from the course or makes botanical training less 

 efficient to present the practical aspects of the subject. 



This book is intended for elementary courses in Botany in 

 colleges and universities. In its preparation the aim has been to 

 present the fundamental principles of Botany with emphasis 

 upon the practical application of these principles. The subject 

 matter is presented in two parts, part I being devoted to the 

 study of the structures and functions chiefly of Flowering Plants, 

 and Part II, to the study of the kinds of plants, relationships, 

 Evolution, Heredity, and Plant Breeding. 



In the preparation of the book, I had the following objects in 

 view: (1) to present the structures and functions of Flowering 



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