“se val 
: 
‘ 
L, Lesquereux on the Coal Formations of N. America. 69 
species have apparently thin leaves or fronds, the name could 
not be preserved of course. -A discussion concerning the mor- 
mention these peculiar forms, for comparing the distribution of 
the genus Hymenophyllites. Two of our American species are 
closely related to the H. elegans Brgt. of Europe. — The others, 
especially H. fimbriatus Lsqx., are gianna peculiar American 
pes. This last, nevertheless, coul be compared to Selaginites 
mani Gutb. 
Alethopteris Sternb.—All our American species have some af- 
finity with European types of the same genus. Even the re- 
