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COMMON SCALE FERN. 
green, living on the limestone, and lodging, when 
away from its native rocks, on any old walls or ruins. 
The stipes is short and scaly ; the fronds are commonly 
pinnatifid, sometimes pinnate, divided rather more 
deeply, The upper surface is a deep opaque green ; 
the under is densely crowded with closely- packed and 
overlapping ‘scales, whose rusty brownness, as they 
project beyond the margin, seen yet more fully in the 
exposed under-surface of the young partially-developed 
fronds, contrasts with the deep green of the upper 
surface. The pinnae or lobes are ovate, either entire 
or lobed in the margin. The venation is indistinct, 
on account of the opacity of the thick and fleshy 
fronds. Indeed, it is only to be made out by examin- 
ing young fronds, removing the scaly- covering, and 
the outer skin of the frond itself. It is then seen 
that the principal vein, entering at the lower corner, 
proceeds sinuously toward the upper side of the apex, 
branching alternately, and branching again, the 
venules becoming more or less joined near the mar- 
gin. The sori are borne irregularly along the sides 
of the venules, most of them directed toward the apex 
of the pinna. At first they are quite hidden by the 
scales, but ultimately the spore-cases protrude between 
them, though, being nearly of the same colour, never 
very obviously. 
In old times this plant had a great medicinal repu- 
tation. Gerard writes of it : — “ There be empiricks 
or blinde practitioners of this age who teach that with 
this herbe not only the hardness and swelling of the 
spleene, but all infirmities of the liver, may be 
