Haunts, Habits, and Distribution. 



23 



V. New Mexican: inhabiting the central mountain re- 

 gions of New Mexico and Colorado, many of the species extend- 

 ing thence into Mexico, and some even to South America, and a 

 few of them also occurring in California. 



VI. Tropical : inhabiting the border of the Gulf of Mexico, 

 most of the species extending into the West Indies and Tropical 

 America." 



21. The distribution of our species can be seen from the fol- 

 lowing table : 



Regions. 



I. Cosmopolitan, 

 II. Boreal 



III. Appalachian, .. 



IV. Pacific 



V. New Mexican,.. 



VI. Tropical, 



Total 



Sub- 

 Varieties. 



Speciespecu- 



HartoNearc- 



tic Realm. 



2 



18 



II 



3 



51 



For the distribution of individual ferns, and for the list of spe- 

 cies peculiar to America, the reader is referred to the description 

 of the species later in this work. Future discoveries will be likely 

 to modify to some extent the limits there given. It will be noticed 

 that those parts of our realm separated farthest from other coun- 

 tries contain the greatest number of peculiar species. 



22. Local Lists. — The number of species found in a single 

 locality is usually limited, yet in certain locations there is a marked 

 diversity. As an instance, in one of the habitats of the rare hart's- 

 tongue,* the writer has collected twenty species illustrating nine 

 genera within the radius of a stone's throw. Such localities, how- 

 ever, are comparatively rare and must include wide diversity of 

 soil and shade within very narrow limits. 



The following table will indicate something of the local distri- 

 bution of species. Carefully prepared lists from all parts of the 



* " Green Pond," near Jameaville, Onondaga County, N. T.. 



