104 
EEBXY COWBES. 
gant. These two latter have only as yet been 
found in Scotland. 
Hymekopeyelttm exilateeaee. Wilson’s 
Filmy Fern. (Plate IV. Pig. 2.) 
The Wymenophyllums resemble the moss tribe 
much more nearly than they do other ferns (with 
the exception of Trichomanes brevisetum ) in general 
appearance; and instead of hearing their seed at 
the hack of the frond, it is concealed in small cupped 
receptacles, which in unilaterole stand on short 
stalks between the main stem and the branches, 
which always turn in one direction, and the recep¬ 
tacles conspicuously in another. In FLymenophyl- 
Imrn Tunbridgense the receptacles are also placed 
between the branch and the main stem, but forms 
as it were a portion of the frond. These two little 
plants are seldom more than two or three inches 
high, with creeping wiry roots, which cling in 
moss-like patches to rocks in the neighbourhood of 
streams, or twine among the mosses they so much 
resemble at a little distance. 
The frond consists of a midrib and alternate 
branches, which are again ramified on the upper 
side ; these branches are clothed with narrow pel¬ 
lucid wings. The most sure distinction between 
the two varieties is the shape of the receptacle. In 
