our ferns ; there is scarcely a heath, common, wood, or forest in
any part of the United Kingdom, in which it does not make its
ajjpearance: its presence in great abundance is said to indicate
poverty in tlie soil, hut I am inclined to think that its absence
from rich and highly cultivated land is rather to be attributed
to the effects of the plough and hoe, than to any quality of the
soil. I t is one of those truly wild plants which fly from man,
and take refuge in wastes and wildernesses. Its size is very
unequal; it varies in height from ten or twelve inches to as
many feet, but its average may be stated at three feet. In
thick shady woods, having a moist soil, it grows to an enormous
s iz e ; hut in dry, gravelly, or sandy soils, it becomes very
diminutive.
The roots are brown, fibrous, and tomentous. The rhizoma is
brown, velvety, and most extensively and rapidly creeping; it
generally runs in a nearly horizontal direction, hut sometimes
dips deeply and almost perpendicularly. When the London and
Croydon Railway was in progress, I found in the New Cross
cutting great abundance of these rhizomata in a decayed state,
some of them extended to a perpendicular depth of fifteen feet.
Whenever this fern has stood unmolested for a long series of
years, the soil becomes filled with a complete net-work of its
rhizomata. The young fronds make their first appearance in
May, they are extremely tender, and the first shoots are almost
invariably destroyed by the late frosts of spring ; I have seen
them cut down to the surface of the ground as late as the 20th
of May. Tlie young fronds come up bent or doubled, the leafy
portion being pressed against the rachis, and not curled in a ring
or circinate as we find it in most of our other ferns : the cut at
the head of the preceding page shows a number of young fronds
in various .stages of development, and also the mode in which
they spring from the rhizoma. The portion of the rachis below
the ground is of a dark brown colour, velvety, and considerably
stouter than the portion above ground; it closely resembles the
rhizoma in its general appearance. When this incrassated
portion of the rachis is cut through, either in a direct or oblique
direction, the section bears a regular figure, as represented in
annexed cut, the left-hand section
being direct, the right-hand oblique.
TJiis figure is by many said to represent
an oak tree, and is called King Charles in the Oak ; by others it
is supposed to resemble a spread eagle, hence the specific name
of Aquilina given it by Linneus. The frond is killed by the
first frosts of autumn, however slight they may he ; it instantly,
turns to a deep brown colour, hut remains periectly undecayed,
and frequently in an erect position during the whole winter.
The form of the frond is nearly that of an equilateral triangle,
the base being somewhat hut not materially the shortest of the
three sides. The naked portion of the rachis is rather more
than a third of the entire length of the frond ; it is green, and
rather pilose, rounded, and not “ angular and sharp-edged,
wounding the hands severely,” as stated in the “ English Flora.
This statement must have crept in by some casual error, not
being at all applicable to the present species. The pinnæ are
pinnate, and the pinnulæ regularly cleft to their midrib, the
lobes being rounded and entire ; the first pinnula on the upper,
side of each pinna being smaller, and often undivided. Under
ordinary circumstances all the fronds are fertile, but the apex of
each frond is commonly barren.
In the fertile pinnulæ the sides of the lobes
are reflexed, the extreme margin being bleached
and ragged, and forming a cover to the thecæ,
which are arranged in a marginal series, and as
they approach maturity are gradually protruded
beyond this cover, and appear in two dark
lines, parallel to the midrib of the lobe, as
represented on the left side of the adjoining
figure. The transverse veins are placed alternately
on the midvein of the lobe ; they are forked almost
immediately on leaving the midvein, and the divisions are not
unfrequently again divided before reaching the margin ; all the
veins are continued to the extreme margin of the green or leafy
part of the lobe, and there enter a pulpy incrassated portion
of the indusium, in which they become divided and disappear
; and from this incrassated part the thecæ take their rise,
as far as I can discover, in a continuous line ; they are placed
between two covers, which I will call indusia, although it is
evident that both cannot be analogous to the indusium, in the
genera Polystichum, &c. These two indusia may be detached
with the thecæ adhering to them : the exterior terminates in
a marginal fringe, or series of capillary segments. Owing to
the great and almost invincible elasticity of the reflexed portion
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