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g row in g y e a r a fter yea r, and so a single plant m a y in time
become a whole colony. C lo se to the g ro w in g end o f the root-
stock is a v e r y short bud, wh ich w ou ld develop into a stalk
and frond in tw o y e a r s ’ t im e : a short distance back o f this is
a bud an inch o r tw o long, a t the top o f which m a y be pla inly
seen the infolded rudimentary frond fo r the n e x t y e a r ; and
back o f this is the s ta lk fo r the frond o f the present yea r.
F a r th e r back still are the d e ca y in g remains o f the stalks which
have supported fronds in prev ious seasons.
T h e stalks h ave the portion beneath the sur fa ce o f the
g ro u nd considerably swollen, and blackened like the root-stock.
T h e y are erect, and sometimes attain to the h eigh t o f severa l
feet abo ve the surface. T h e i r color is com m on ly a dull
red d ish -b row n , sometimes a pale s t raw -co lo r . T h e sur fa ce is
devoid o f chaff, and the anterior side is moderately furrowed.
A c ro s s -se c t io n show s a central m a s s o f sclerenchyma, in
w h ich there are about three n a rrow r idges projecting anteriorly
and tw o po ster io rly from a transve r se b a n d ; between these
ridges are o v a l o r flattened isolated bands o f f ib ro -v a s cu la r
tissue, and numerous sm a ller threads o f the sam e tis su e su r round
the w h o le central mass. T h i s is the stru ctu re o f a v e r y
y o u n g stalk, and m a y perhaps v a r y a little a s the sta lk s become
mature. T h e w h o le appearance o f the section has been
likened to the heraldic "d isp la y e d e a g le ;” and one o f the
common names a s w e ll as the specific name, has reference to
this resemblance. B u t it is a lso said that K in g C h a r les in the
O ak m a y be seen in the stem o f the bracken.
T h e frond is broadly o vate-trian gula r in outline, the breadth
being ne ar ly o r quite equal to the length. The size va r ie s
m uch according to soil, climate, etc. ; so that while plants m a y
be mature, and y e t h ave fronds less than a foot high, th ey frequ
en tly are found from three to five feet high. T h e s e dimensions
are exceeded in Oregon, wh e re the bracken fo rm s thickets
s ix or seven feet high. H o o k e r and B a k e r report that Dr.
S p ru c e has seen it fourteen feet h igh in the A n d e s . T h e rachis
o f the frond bends aw a y a bru p tly from the top of the stalk,
and the short petioles o f the tw o low e s t pr im a ry pinnæ bend
similarly , but in other directions. T h e effect is to make the
frond spread obliquely in three different directions, a pecu lia rity
w h ich is lo st when specimens are pressed fo r the herbarium.
V e r y la rg e fronds are fa ir ly tripinnate a t the b a se ; sm a ller ones
o n ly bipinnate. A b o v e the base o f the frond the p r im a ry pinnæ
rapidly become smaller, so that the pinnæ of the fifth pair
a re about the sam e size and degree o f composition a s the
low e s t secon dary pinnæ of the low e s t p r im a ry pinnæ. T h e second
ary pinnæ are oblong lanceolate, n e ar ly sessile, and u su a lly
pinnatifid a lmost to the midrib into numerous rather obtuse
oblong segments, besides a terminal segment, which is often
much lon ger than an y o f the lateral ones. S om e t im e s the
side lobes are reduced to a sin gle basal pair, and the pinna is
then hastate, and aga in the lobes m a y be en tirely separated,
and thus become distinct entire pinnules. T h e ultima te s e g ments,
or lobes, are so v a r iable in length and breadth, that it
is not e a sy to g iv e a ve ra g e measurements. B u t it may, per-
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