PREFACE 



In the present volume an attempt has been made to acquaint 

 the reader with the more essential aspects of the subject. Espe- 

 cially have we had in mind a purpose to make familiar our 

 common plants which knowledge we believe to be fundamental 

 in any botanical work. In a word the work is designed to 

 give the reader a view point. It is not put forth as a text- 

 book but it is hoped that the discussion will give the student 

 such a comprehension of the subject that he will come to the 

 lecture room in a proper attitude and that he will approach his 

 laboratory work with a desire for investigation. If the book 

 shall quicken the reasoning faculty, and create a desire for 

 further examination of the subject, its object will have been 

 fulfilled. 



Acknowledgments are made to Professors L. M. Underwood, 

 H. M. Richards, T. E. Hazen and to Doctors G. G. Scott and 

 Chester A. Darling, for valuable assistance in the preparation of 

 various portions of the text. The author desires to express his 

 especial indebtedness to his good friend, Mr. H. O. Hanson, for 

 the preparation of many of the illustrations, to Mr. W. A. 

 Andrews for microscopical studies from which drawings have 

 been made and to Miss Mary L. Williams for the execution of 

 many of the drawings. 



CARLTON C. CURTIS. 



COLUMBIA UNIVERSITY, 

 August, 1907. 



