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immediately after leaving the mid- vein that the anterior 
branch bears an elongate linear mass of rust-coloured thecte ; 
this, when young, is covered by a white membranous 
indusium of the same shape as the mass, uniformly opening 
towards the apex of the frond. 
Beware, young -botanist, while seeking for this fern in 
marine caverns, or in the fissures of sea-cliffs, that you 
make yourselves acquainted with the time when the tide 
rises from day to day. You may otherwise have to wade 
amid the dashing spray, or else to peril life and limb, in 
climbing up the slippery sides of rocks, with your hard- 
earned treasures in your hands ; happy, if you escape passing 
the night on some high crag, which barely affords you a safe 
standing-place above the strife of waters. 
GREEN SPLEENWORT. 
The geographical range of the Green Spleenwort, Asplenium 
viride of authors, A. trichomanes of Linnseus, is very limited. 
In Ireland it is believed to be confined to a single mountain 
Ben Bulben ; in this country to the extreme northern 
