M
i J ü
t - ; i •
K M
r - ’ '
» •
. I'
- r i i
| i . .
' «-
r #
ft
» . i
E .
i
e
► »
i f
. J l
i v
198 FERNS OF NORTH AMERICA.
Polypodium ceteraccinum, M ic h a u x , F 1. Bor, Am., ii., p. 2 7 1 .
Polypodium Eckloni, K u n z e , in Linnæa, x., p. 498. — M e t i 'en iu s , Polypodium,
p. 68. — H o o k e r , Sp. F i l , iv., p . 209.
Polypodium incanoides, FÉE, 8'"' Mém., p. 8 8 ; Foug. Mex., p. 20, n. 12.
Acrostichum polypodioides, L in n æ u s , Sp. Pl., p . 1525.
Acrostichum fronde pinnata : fo lio lis linearibus alternis sessilibus, termi-
natrice plerumque trifida, G ronoviu s , F 1. Virg., p . 19 8 .
H ab. — On trunks of trees and on old roofs, more rarely on rocks,
from Florida to Texas, and extending northwards to the Natural Bridge,
Virginia, M e e h a n , Wirt County, West Virginia, H. N. M e r t z , and to a
few places in the southern parts of Ohio, Indiana, and Illinois. Common
in the West Indies, and from Mexico to Brazil and Chili. Also
in South Africa and in Tropical East Africa.
D e s c r i p t io n . — The gray polypody, hoary polypody, or scaly
polypody, as it has been variously called, though properly a tropical
fern, yet occurs so far north, that it must occasionally have to
withstand a severe frost. It commonly grows in large mats, the
creeping root-stocks very much entangled. These root-stocks
are about a line and a half in thickness, and are at first covered
with ovate-acuminate scales, which are peltately attached
near the base, and have a dark-brown rigid median band surrounded
by a hyaline laciniately ciliate border. Afterwards the
border wears away, then the long point of the scale breaks off,
and at last the root-stock is left nearly bare. The stalks are
slender, and are at first covered with scales like those of the
root-stock ; but these fall off, and there remain ovate and rounded
scales intermixed, all with a dark centre and a nearly transparent
) • -
FERNS OF NORTH AMERICA. 199
border. The fronds have a leathery texture, are dark-green in
color, nearly or quite smooth above, and beneath copiously
sprinkled with scales like those of the stalk, the rounded ones
predominating. In many tropical American plants, however, the
fronds bear an abundance of long-pointed scales. The fronds
are capable of withstanding drought, and are often found curled
up, and apparently dead; but when they are moistened they uncoil
themselves, and are as fresh and green as ever. They are commonly
in the United States about three inches long, and nearly
half as wide ; but fronds both much smaller and considerably
larger are often seen, especially in foreign specimens. The segments
are from four to twenty on each side, oblong-linear or
sometimes a little obovate in shape, entire, and obtuse, the lowest
ones rarely a little shorter than the middle ones. They are
separated by rounded bays which reach quite to the midrib.
The venation varies in different plants, and is difficult to
be seen, as the fronds are very opaque; it is, however, generally
free, each vein forked near the base, the upper veinlet simple, and
the lower one again forked; but occasionally, especially in tropical
plants, the veinlets are united near the margin, forming areoles.
The fruit-dots are rather small, round and naked, and placed at
the end of the upper forks of the veins; and, as the segments
of the fronds are often made concave by drought, the fruit-dots
appear to be marginal. The spores are light-colored, ovoid-bcan-
shaped, indistinctly vittatc along one side, the surface sprinkled
with minute pale-yellowish granules.
This little fern is by no means particular in its choice of a
i '
J :■