AUTHOR'S PREFACE. 



IN the preparation of these outlines it is recognized 

 that a given set of directions is not completely adequate 

 for the work of any two teachers, nor even for one 

 teacher's use during two consecutive years. A good 

 instructor is the chief determinant in a course of study. 

 In his hands the materials, the laboratory, and the book 

 become efficient in the presentation of the subject. To 

 his students the laboratory guide serves as an outline to 

 which he makes additions as determined by the immedi- 

 ate needs of his own class. It is rather generally recog- 

 nized that a course of study in botany may be made much 

 stronger if a well- organized plan is placed before the 

 students, since a good instructor can make requisite 

 eliminations and additions to fit his peculiar needs, and 

 all by means of the laboratory guide may have the advan- 

 tage of the accumulated experience of others. The 

 wide field of usefulness that was filled by Plant Dis- 

 section furnishes abundant evidence as to the value of 

 a good laboratory guide. It was in response to a belief 

 that a new book which embodies the general arrange- 

 ment and some of the important principles of the old one 

 will be correspondingly useful, that the authors of Plant 

 Dissection suggested the preparation of this work. 



