F E R N S ;
B R IT ISH AND EXOTIC.
P T E E I D E i E . J . S m i t h .
T h i s extensive class of F e rn s contains the genus ITypolopis,
species with large and handsome fronds; th e genus Chcilanthes,
a v ery p re tty trib e of plants, some of which are covered
b eneath the frond with dense farinose pow d e r; P la ty lom a , a
very various and handsome trib e ; A d ia n tum , known generally
as th e Ma idcn-hair F e rn s, th e most dclicate-looking of any
trib e ; Litohrochia, an extensive gen u s; P te r is , mostly large and
elegant F e rn s ; Onychium, s. small b u t interesting family; Lomaria,
having fertile fronds different in form from th e b a rre n fronds;
Blcchnum and Doodia, singular F e rn s ; and Woodwardia, a
small b u t elegant genus.
I n the Pteridece th e sori are circular or elongated, and tran sverse,
marginal, in trama rginal or costal, simple, except when they
become confluent, when they are compound. The sori have a
special la te ra l indusium, which is p roduced on the exterior side
of the sporangiferous receptacle. I ts inn e r margin is free.
The Pterideai are at once known from th e Polypodiacece by
the special indusium.
VOL. III.