78 A S P ID IU M D IL A T A T U M .
Aspidium dilatatum,
spinulosum,
“ erosum.
Polypodium tanacetifolium,
Polystichum tanacetifolium,
Polypodium aristatum,
Lastrea multijlora var. nana,
“ dilatata var. nana,
Lophodium multijiorum, \
var. nana, 3
Aspidium dumetorum,
Lifslf'ea dumetorum,
“ dilatata var. collina,
“ “ var. maculata,
“ multijiora var. collina,
collina,
“ maculata,
Lophodium collinum,
Lastrea dilatata var. collina,
“ multijlora var. collina,
“ collina,
Lophodium coUlnum,
Lastrea Chanterice,
“ dilatata var. angusta,
** alpina,
“ dilatata var. glandulosa,
“ glandulosa,
Lophodium glandulosum,
‘ ‘ gland a liferu m,
W i l l d e n o w .
S p r e n g e l .
S c riK U H R .
SCIIKUHK.
H o f f m a n n .
D e C a n d o l l e .
ViLLARS.
H e w m a n . D e a k in .
M o o r e .
H e w m a n .
S m i t h .
M o o r e .
M o o r e .
M o o e e .
H EWMAN.
H e W-MAN.
D e a k in .
H e w m a n .
M o o r e . B a b i n g t o n .
Variety
H e w m a n .
N e w m a n .
N e w m a n .
M o o r e .
M o o r e .
M o o r e .
M o o r e .
N e w m a n .
N e w m a n .
N e w m a n .
D e a k in .
T a n a cttifo lium .
' Var. Nanum.
Variety
Dumetorum.
Vai'iety
Colliiiuni.
Variety Chanterice.
Variety Angustum.
Variety Alpinum.
> Variety Glandulosum.
Aspidium—The Shield Fern. Dilatatum—Extended.
l i t THE S e c t io n L a s t r e a o f A u t h o r s .
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A S P E C IE S subject to great variety. Aspidium dilatatum,
the “ Broad Prickly-toothed Buckler F e rn ,” is a noble British
species; easily cultivated, and of large growth.
A hardy deciduous Fern, growing in shady situations, and
to be met with almost everywhere. The variety tanacetifolium
is also common; the other varieties are local.
I t is dispersed throughout the whole of Europe, from L ap land
to Portugal and Spain. In Asia, in Kamtschatka; in
A S P ID IU M D I I .A T A T U M . 79
Africa, in the Azores; in America, at Sitka, Port Mulgrave,
Canada, and the Rocky Mountains.
The ordinary form is ovate-lanccolate ; bipinnate to tripinnate.
Pinnæ opposite, numerous, the basal pair obliquely triangular-
elongate; the posterior pinnules considerably larger than the
anterior pinnules. The pinnæ taper gradually from the base
to the apex. Pinnules ovate-oblong, rather acute, the basal
ones stalked, and the upper pinnules sessile and decurrent,
the lower ones deeply pinnatifid, occasionally pinnate. The
divisions are all sharply dentate, ending in a hristle-like
point.
Veins forked.
Caudex stout, mostly uprig h t; crown densely scaly.
Stipes terminal, from a third to half the length of the
frond ; densely scaly.
Fructification occupying the whole of the under side of the
frond. Sori numerous, circular, and indusiate. Indusium
reniform and membranous.
Length from two to six feet, usual size from two to three
feet; breadth from six to sixteen inches. Colour dark green
above, paler beneath.
One of the most difficult species to under.stand, as in its
different forms it approaches both A . fcenisecii and A . spinulosum;
from the latter it is known by A . spinulosum having
a creeping caudex, the few broad pallid scales of its stipes, and
by the indusium being entire.
The form tanacetifolium, or “ Tansy-leaved prickly-tootbed
Buckler F e rn ,” is tripinnate, with broad fronds; stipes having
numerous entire dark brown scales, with a darker bar down
the centre; lanceolate in form.
The form nanum, or “ Dwarf prickly-toothed Buckler F e rn ,”
from Settle and Ilfracombe, is always dwarf, varying from two
to ten inches in length.
The form dumetorum, or “ Thicket prickly-toothed Buckler
F e rn ,” is also dwarf, with broad frond, having large abundant
fructification, and is remarkable for the glandular surface of
the fronds.
The foi-m collimm, the “ Hill prickly-toothed Buckler F e rn ,”
known also as “ Binder’s F e rn ,” has the pinnæ distant and
spreading.
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