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quickly lose their vitality, and are cast off at the articulation
or joint near the base of the stipes, which occurs in this
family. The Alpine Woodsia, like its congener, grows in a
tufted manner, sending up several fronds from the crown,
from the base of which the dark-coloured wiry roots are
protruded. In form these fronds are longish and comparatively
very narrow, almost linear, as it is termed ; and they
are pinnately divided into several roundish triangular pinnæ,
which are shallowly lobed on the margin, and are usually
set 'on alternately along the opposite sides of the stalk or
rachis ; those towards the lower part are usually placed at a
greater distance apart than those near the upper end. They
are nearly smooth on the surface, and, in this respect, unlike
those of the kindred species, which have a much more hairy
appearance ; small hair-like scales, in company with hairs,
are, however, present in both species.
The midvein of the pinnæ is indistinct, and throws out
venules into each lobe, these venules being more or less
branched according to the size of the lobes. The sori are
placed near the extremity of the venules, and are often
abundantly produced, so as to become crowded on the
pinnæ.
The Alpine Woodsia is named W. alpina, by Mr. Newman
; and has formerly been called Acrostichum alpinum,
Acrostichum hyperioreum, Polypodium hyperioreum, and
Polypodium arvonicum.
The two English Woodsias are in Great Britain found
only in high mountain regions, where they grow from the
crevices of the moistened rocks. They are both rare, though,
from the inaccessible localities in which only they occur,
they may really be more abundant than is generally supposed.
Both also appear to be confined to the northern
parts of onr hemisphere.
Erom their rarity rather than their beauty these form
interesting pot-plants. They require to be kept in a cold
shady frame, to be potted in very porous soil, and to be
carefully guarded against drought or stagnant moisture.
W o o d s ia il v e n s i s , R. Brown.— The Oblong Woodsia.
(Elate I II. fig. 2.)
A deciduous species, dpng down to the ground annually
in winter, and reviving with the returning spring. Its very
short stems form tufts, which, if not disturbed, and are
situated under favourable circumstances, grow into large
masses, speaking comparatively with its diminutive stature.
The fronds average about four inches in height, and are less
frequently found larger than smaller than this. Their form.