308 KEY TO THE GENERA. 
#. Sori near the margins. Indusia 
formed by the reflexed edges of the 
pinnules, 
c. Sporangia in a contznuous line; 
fronds large, zermate; indusium 
narrow. Bracken, PTERIS, 
e. Sporangia in od/ong or lunate 
sori, under a@ reflexcd tooth of the 
pinnule; indusium broad ; stipe and 
rachis dark and shining. Maiden- 
hair, ‘ é ADIANTUM, 
c. Sporangia in roundish masses. 
t Indusium éroad, nearly continu- 
ous ; fronds smooth ; stipes usually 
dark; rock species. Cliff brakes, 
PELL@aA, 
Pellea 
{ Indusium zarrowwer, seldom con- 
tinuous, often zzcousptcuous , 
fronds usually hairy. 
CHEILANTHES, 
+ Indusium of the reflered edges, 
at first reaching nearly Zo the mzd- 
rz6, later nearly flat ; fruiting pin- 
nules, long, podl/zke , sterile fronds 
broad; stipes pale. Rock brakes. 
CRYPTOGRAMMA. 
PAGE. 
69 
242 
xe 73 
257 
287 
