THE BLADDER FERNS. 
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introduced to keep stagnation from the roots of 
the plant by the filtration of the water through the 
drainage of broken flower-pot or bricks. Like 
Cystopteris fragilis our little Cystopteris regia has 
a tufted root-stock, from which spring up clusters 
of beautiful, delicate, herbaceous, charmingly-green 
fronds. 
3. THE MOUNTAIN BLADDER FERN. 
Cystopteris Montana. 
One of the very rarest of our rarer native species 
is the Mountain Bladder Fern, found only in one 
or two localities in the Highlands of Scotland. It 
has a creeping root, which finds its way underneath 
the moss and other vegetation, amongst which the 
charming little plant grows. Its fronds are re- 
markably distinct from those of the other species 
of Bladder Ferns which occur in this country. 
The stipes is about twice the length of the leafy 
portion of the frond, the entire length of which is, 
however, rarely found to be more than some eight 
