GENERA AND SPECIES. 123 
PLATE XLVIII. (Frontispiece.) 
TRICHOMANES RADICANS. Swartz. 
BRISTLE FERN. KILLARNEY FERN. 
This exceedingly rare fern has a black, wiry, creeping 
root-stock, with somewhat drooping fronds of very variable 
outline. The texture of the leafy portion is thin and deli- 
cate, with the veins surrounded by a sort of pellucid fringe, 
as in all the filmy ferns (Hymenophyllacez). The plant is 
from three to ten inches high. The leaf-stalks have a 
kind of membranaceous keel or wing, and are smooth or 
somewhat rusty. 
The name of Killarney Fern was given to it by the 
English botanists on account of its being found, in Great 
Britain, only in the neighborhood of the Lakes of Killarney, 
Ireland. Previous to 1872 it had only been reported as 
found in Alabama and Tennessee (Gray), in this country; 
but in that year it was discovered in Carter County, Ky., 
by Dr. H. H. Hill, of Cincinnati. Carter County is in the 
northeastern portion of the State, near the borders of West 
Virginia. In the years 1873 and 1874 it was collected by 
Prof. Hussey in the same county, and in Edmonson and 
Barren counties. In Barren County, Prof. Hussey says 
that he “found it in more than twenty localities, always 
on rocks or moist earth, far under overhanging cliffs, at 
least where moisture never fails, and the direct rays of 
the sun do not reach during many minutes of the day. 
Usually the fronds are bedewed with moisture trickling 
from the rocks on which they grow.” 
In 1876 Mrs. L. P. Yandell, of this city, found it in 
Laurel County, near Rockcastle Springs. In a letter to 
the author she thus describes the place where it was found: 
