45 



specimens he left to tell of his earnest labor as a botanist, 

 I should think he had noticed about two-thirds of our 

 county ferns. 



The arrangement in this paper is according to Gray's 

 botany, fifth edition, where full descriptions of each 

 species will be found. 1 



We have represented in the county, so far as is now 

 known, sixteen genera, including twenty-nine species and 

 about eight book varieties. A very few species may 

 possibly be added after a careful search, but that is ex- 

 tremely doubtful. 



I will take these species in order, and notice each sep- 

 arately, commencing with : 



1. ONOCLEA SENSIBILIS L. 



Sensitive Fern. 



So called oil account of the habit of quickly turning black after the 

 first frosts. The fertile and sterile fronds are entirely different in ap- 

 pearance, the former not showing themselves till August and then 

 becoming rigid and remaining perfect almost through a second season, 

 while the sterile fronds commence to unfold early in May, are very 

 broad, and perish at the first frost. Common everywhere. 



2. A very curious abnormal form is the var. obtuselobata of Torrey, 

 not a true variety but only an occasional state of a frond of the ordi- 

 nary plant. This illustrates how the sterile and fertile fronds in 

 dimorphous ferns can be shown to resemble each other and is only a 

 half-way state between sterile and fertile, so to speak. Frequent, 



with No. 1. 







3. STRUTHIOPTKRIS GERMANICA Willd. 



Ostrich Fern. 



\ 



This is the tallest of all New England ferns, growing to a height 

 of six feet, and yet it is one of.the most graceful of our species. It 

 is not coarse, and spreads by numerous underground runners, filling 

 whole fields in parts of New Hampshire and Vermont, where I have 



1 It should be noted that this paper was illustrated by perfect herbarium speci- 

 mens of each species and variety referred to, rendering botanical descriptions 

 unnecessary. English names are added for each species, though many are poor 

 enough. 



