— Ill — 



For ten years or more after the publication of these 

 lists interest in ferns appears to have slumbered. It was 

 awakened by the publication in 1895 of the modest little 

 " Bulletin Xo. 9 " of the Linnean Fern Chapter, under 

 the editorship of the present writer. Its full title was 

 "The Pteridophyta of North America." This list was 

 consecutively numbered, gave the geographical distribu- 

 tion of each species and so far as known was the first 

 list in America to include the fern allies. As an indi- 

 cation of the trend of study since, it may be added that 

 no subsequent list has omitted them. 



At the time the Fern Chapter list was issued, it was 

 felt that it was not adequate to the needs of collectors, 

 and shortly thereafter William R. Maxon at the sug- 

 gestion of the writer began a new list which was finally 

 published in 1901 in the " Proceedings of the U. S. Na- 

 tional Museum " under the title of " A List of the Ferns 

 and Fern Allies of Xorth America.'' This list is not con- 

 secutively numbered, but gives the principal synonyms of 

 the species and very careful data regarding distribution. 

 It is the only list thus far issued that uses the " new " 

 nomenclature and .is based on a radical conception of 

 species. 



Mr. B. D. Gilbert's " Xorth American Pteridophytes " 

 also appeared in 1901. This list is the exact opposite of 

 Maxon's list in matters of nomenclature and the limita- 

 tion of species and much excels that work in the number 

 of forms and varieties included. It is consecutively num- 

 bered and has served as the standard for most of the 

 exchanging that has been carried on since. 



In presenting a new list I have been actuated not only 

 by the fact that all these lists except Mr. Gilbert's is out 

 of print, while the demand continues to increase, but by 

 the fact that a large number of species and varieties have 

 been named since that list was issued, necessitating a list 

 brought down to date. I have attempted to include in 

 this list every species, sub-species and form that has been 

 described from the region. All of these are listed in 

 black-face type. Synonyms are in italic and are separated 



