a AMERICAN FERN JOURNAL 
Type in the U. 8. National Herbarium, no. 579209, col- 
lected near Cana, Panama, April 17 to June 8, 1908, by 
R. 8. Williams, no. 917. 
D. Williamsii is related to D. orthoclada (Christ) 
_ Underw. of the interior mountain region of Costa Rica, a 
species which differs widely in its glabrous condition 
_ throughout, its shorter and broader branches, its some- — = 
what flexuous rachises, its few and conspicuously sur- 
current segments, its much heavier costae, and its widely — 
-anched veins. 
The peculiar morphology of the family Gleicheniaceae, — 
represented in America by the genus Dicranopteris, 15 
discussed at some length in a paper by Dr. Underwood, a 
which is doubtless available to many members of the 
American Fern Society. Most of the species grow on 
n, Open or partially shaded slopes, often in very 
Savages and mine dense, tangled thickets of 
