PREFACE 5 



manuscript and has given it most careful criticism ; and to my 

 colleagues in the High School of Commerce, Messrs. Matthew- 

 son, Barbour, A. II. Lewis, Sprague, and Hahn, who have ren- 

 dered substantial assistance in the preparation of this book, 

 I desire to express my sincerest thanks. 



The following texts have been freely consulted : Bailey, 

 Principles of Agriculture, Plant Breeding, and Botany; The 

 Cornell University Bulletins; Osterhaut, Experiments with 

 Plants; Percival, Agricultural Botany ; United States Depart- 

 ment of Agriculture Bulletins, and the botanical textbooks of 

 Andrews, Atkinson, Bergen, Coulter, Barnes, and Cowles, Dana, 

 Goff and Mayne, Goodale, Gray, Hunter, Leavitt, and Sharpe. 



