viii Preface. 



4. As in all specialties, works treating exclusively on ferns 

 either structurally or systematically, are rare and expensive. 

 Previous to 1877 no work on the subject of ferns had been pub- 

 lished in America, and to this date no manual available to students 

 has been issued that classifies all our native species or outlines 

 their morphology and mode of life. 



The design in issuing this little volume is to furnish to those 

 desiring a better understanding of ferns the means of gaining a 

 knowledge of their structure and life, and of readily determining 

 the species growing spontaneously in North America north of 

 the Mexican boundary. If the work succeeds m rendering assist- 

 ance to any already interested in the subject, or in stimulating any 

 to commence a systematic and scientific study of this most attrac- 

 tive botanical order, the writer will feel abundantly repaid. 



In the preparation of chapters IV. and V., Sachs' Lehrbuch has 

 been frequently consulted. The descriptions of our native ferns 

 have been collected from various sources. Hooker's Synopsis 

 Filicum and the papers by Prof. Eaton in Gray's Manual, Chap- 

 man's Flora, and "The Ferns of the Southwest " have furnished 

 much of the material. In Botrychiiim the valuable papers by 

 George E. Davenport have furnished many additions, especially 

 respecting the method of vernation. In addition, the original 

 descriptions of various authors and the large private collection 

 of the writer have been freely consulted, with the hope of making 

 the work in every way a satisfactory manual for identifying 

 species. 



The grouping of species is in part my own, but in a few cases 

 that of other authors has been adopted. The " Artificial Synopsis 

 of Genera " has cost much labor, and though in some respects 

 is still unsatisfactory, it may be found useful for distinguishing 

 genera. Synonyms are given only where recent changes in 

 nomenclature have been made. 



No. attempt has been made to popularize the language of the 

 work at the expense of scientific accuracy, the writer fully be- 

 lieving that if this subject pr any other department of the natural 



