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HISTORY OF BRITISH FERNS. 
Genus XVIIL BOTRYCHIUM, or MOONWOBT. 
This small and very distinct plant is easily known by 
two circumstances, — first, it has two fronds or rather two 
branches of its frond, the one of which is leafy, the other 
seed-bearing ; and secondly, the pinnae of the leafy branch 
are crescent-shaped, with the outer margin jagged. There 
is no other native plant which has these peculiar features, 
and hence the Moonwort is a plant very easily recognized 
when it is met with. It is rather local in its range, but 
not scarce in the localities where it is found, which are 
open heaths and pastures, rather dry than otherwise. The 
spore-cases are collected into branched clusters at the end 
of the fertile branch ; the little branches of the cluster 
are all turned one way, and the spore-cases themselves 
are numerous and globular, and somewhat resemble in the 
aggregate a miniature erect bunch of grapes. 
There is another peculiarity in this Fern which also 
serves to distinguish it, and its near ally the Ophioglossum^ 
from all other native species — the venation is straight, not 
circinate ; that is, the fronds, before they are developed. 
