" i r
| 7 - ; 1
Î %
I*. i
v i i
i> . ” 1.
r -
‘ . r i '
r * - '
i » . A
« M
I» lì
I I ' ’ ’ '
^ 8 8 FERNS OF N O R TH AMERICA.
Nephrodium Plumula, P r e s l , Reliq. Haenk., p. 33.
Polystichum Plumula, P r e s l , Tent. Pterid., p . 8 3 .
Aspidium acrostichoides. H o o k e r , in Bentham, Plant. Hartweg., p. 3 4 2 , not
of Swartz, nor of Hooker in Sp. Fil.
Polystichum falcinellum,^. M oo re , Ind. Fil., p. 97.
Var. nudatum : — FroxiA smaller, the chaff almost entirely lacking;
pinnæ few and rather remote, short and broad, oblong-oval, slightly
auricled, the teeth closely appressed; sori scanty, confined to the ends
of the few highest pinnæ.
Var. imbricans : — Frond below medium size, not narrowed at the
base ; pinnæ crowded, lanceolate-oblong, pale, ascending, and imbricated ;
sori sub-marginal ; stalk with lance-acuminate shining brown scales at the
base, otherwise almost naked, as are the rachis and frond.
Var. inciso-serrahtm r— Fronà ample; pinnæ lance-acuminate from
a conspicuously auricled base, incised with serrated teeth ; veins branched
into five or six veinlets ; sori scattered.
H a b . Described by Kaulfuss in 18 2 4 from specimens collected near
San Francisco in 1 8 1 6 by A d e l b e r t von C hamis so . It is said, however,
to have been gathered many years before at Nutka Sound by A rc h ib a ld
M e n z ie s . It is found among rocks and in forests, sometimes very abundantly,
from Guadalupe Island and San Diego, California, northward to
British Columbia, but not known east of the Sierra. The finest specimens
are from forests near the coast, from Mendocino County, California,
to Southern Oregon. Var. nudatum was collected at the Nevada Fall,
Yosemite Valley, by Professor W ood. Var. imbricans, in Plumas County,
by Mrs. A u st in , at Red Mountain, Mendocino County, Dr. K e l lo g g , and
is probably not uncommon. A form connecting these two varieties was
found in the Trinity-River mountains by Professor W ood, and at Moore's
y
FERNS OF NORTH AMERICA. 189
Flat, Yuba River, by an unknown collector. Var. inciso-serratum comes
from British Columbia, Dr. L y a l l and Professor M acoun.
D e s c r i p t i o n . — Chamisso’s shield-fern, as it may appropriately
be called, is, when well grown and fully fruited, one of
the very finest of the North-American ferns. The root-stock
is short and thick, and covered with the remains of old stalks,
as in most of our Aspidia. The fronds stand in a crown, or
circle, and measure from one to five feet high, according to the
strength of the plant, and the nature of the climate and soil
where it occurs. From one-sixth to one-fourth of this height
is in the stalk, which is strong, rounded at the back, and has,
when living, a broad shallow channel in front ; but in the
dried specimen the furrow is deep and narrow. A section shows
a broad exterior band of firm tissue, and five interior roundish
fibro-vascular bundles, arranged in a curve of two-thirds of a
circle, the bundles at the ends of the curve much larger than
the other three.
The stalk and rachis are usually very chaffy ; but the chaff
is nearly or quite wanting, except at the base of the stalk, in the
first two varieties named above. The chaff consists of bright-
brown ovate-lanceolate acuminate scales, nine to twelve lines
long, constantly growing smaller upwards, and intermixed with
others very much smaller. The large basal scales appear to
have an entire edge, and are usually of one shade of bright
glossy brown ; but sometimes they are heavier, and with a broad
dark-brown median band. The smaller scales are more or less
laciniately ciliate, and those of the upper part of the rachis are
regularly ciliated.
r i i
f-
«
; Iv
i*
b
4
V i tl ii.i
< < I
■ k
I f
!' *
) '
T ?
1 1
I , j