VI PREFACE. 



Acknowledgments are here rendered to those who have aided 

 in the preparation of this edition. Especially we would men- 

 tion Dr. Sereno Watson, of the Botanic Gardens at Cambridge 

 for access to numerous specimens ; Professor Daniel C. Eaton, 

 of Yale, for elucidating the synonymy of Aspidtum patulum ; 

 and most of all, Mr. George E. Davenport for very many kindly 

 suggestions, specimens, and courtesies extending through a 

 series of years. 



SYRACUSE UNIVERSITY, 

 Feb. 18, 1888. 



PREFACE TO FOURTH EDITION. 



IN the present edition several changes have been made with 

 the purpose of bringing the subject-matter to date. Four ad- 

 ditional species have been found in our territory since the last 

 edition was issued, bringing the total number in our flora to 

 228. Additional matter has been inserted in the text and 

 Chapter VIII has been rewritten in order to bring the classifi- 

 cation of the lower plants more in accord with our present 

 knowledge. The most notable change will be found in the 

 nomenclature, which has been revised according to the prin- 

 ciples adopted by the American botanists at their meeting 

 at Rochester in August 1892. While many will regret the 

 change of names long familiar, all will see the justice and pro- 

 priety of the changes. These, however, are not very extensive 

 except in the genus Aspidium, and in this case it will be 

 remembered that the greater part of the species have always 

 been separated by the English botanists under a distinct genus. 



DE PAUW UNIVERSITY, 

 June i, 1893. 



