122 FERNS OF KENTUCKY. 
of the sun. I have found species of the Hymenophyllum 
on the island of Arran, Scotland, growing in localities simi- 
lar to those occupied by the Trichomanes radicans in this 
country. 
Figures 2, 3, and 4 give microscopic views of the urn- 
shaped involucre, sporangia, and spore. The drawing is 
from that of Mr. Bauer, in Hooker and Bauer’s “Genera 
of Ferns.” After a careful examination of the specimens 
found in Kentucky, I can see no difference in them from 
the representations by Mr. Bauer, except that in our speci- 
mens the column seems to arise from the thickened cellular 
tissue a little above the base of the involucre. 
