iy PREFACE. 



rally great difference of opinion among practical teachers. 

 Theoretically it would seem best to begin with the lowest 

 forms of plants, and work up to the higher; but after 

 careful consideration, and in view of the actual state of 

 things in most of our preparatory schools, a different plan 

 has been adopted. 



It is hoped that in spite of mistakes and imperfections, 

 sure to be brought to light if the book is used, it may never- 

 theless prove serviceable to a rapidly increasing number 

 of teachers who are desirous of improving existing methods 

 of instruction. To Dr. Erwin F. Smith of Washington, 

 D.C., and Miss Effie A. Southworth of Barnard College, 

 who have kindly read the proofs throughout ; to Mr. 

 W. H. Rush of the University of Michigan, who has criti- 

 cally reviewed and tested the practical directions; and 

 to others who have aided in various ways, the sincere 

 thanks of the writer are due. 



