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THE FERN FAMILIES OF BRITAIN. 
of three halls, which those of the Limestone Polypody do 
not do. 
The Oak Fern makes itself at home in any open, well- 
drained compost, its slender, creeping rootstalk, branching in 
all directions just below the surface, and speedily taking 
possession of the pot, or, better still, shallow pan, in which it 
is located. On rockwork it soon establishes itself in the 
chinks and crevices, and though, as if being fully satisfied 
with itself, it has disdained to present us with any variations, 
every collection worthy the name must find a place for it. It 
is perfectly deciduous, and needs shelter from wind to display 
its graces fairly. 
The Limestone Polypody 
(Polypodium calcareum. Syn. P. Robertianum). 
This differs from the preceding very little, and the points 
of dissimilarity have already been indicated. As its name 
implies, it grows in the chinks and cracks of calcareous 
rocks, and hence in cultivation requires some admixture of 
lime in the soil. In all other respects, the remarks on the 
Oak Fern apply to this. No varieties. 
The Beech Fern 
(Polypodium Phegopteris). 
Why this Fern is so named we cannot conjecture, and 
should like to know. It frequents similar habitats to the 
Oak Fern, and runs about in a precisely similar manner; the 
same method of cultivation consequently applies. This Fern 
approaches the Lastrea type in the form of its fronds 
(which, however, have a longer stalk), and may infallibly 
be known by the peculiarity that the two lower pinnae, which 
are long, are turned sharply downwards at an angle of about 
45deg., while all the rest are about at right angles to the 
central stalk. The colour is a very delicate green, somewhat 
akin to that of the Oak Fern. The twice-divided fronds are 
Gin. to 9in. long, prettily pendent on the long stalks. Of this 
Fern we have one variety, 
