ady fern is very easy to cultivate and when once established is apt to
crowd aside its neighbors.

(3) SILVERY SPLEENWORT. ATHYRIUM ACROSTICHOIDES

_Asplenium acrostichoides. Asplenium thelypteroides_

Fronds two to four feet tall, pinnate, tapering both ways from the middle.
Pinnae deeply pinnatifid, linear-lanceolate, acuminate. Lobes oblong,
obtuse, minutely toothed, each bearing two rows of oblong or linear
fruit-dots. Indusium silvery when young.

[Illustration: Silvery Spleenwort. _Athyrium acrostichoides_]

[Illustration: Silvery Spleenwort. Athyrium acrostichoides]

The sterile fronds come up first and the taller, fertile ones do not appear
until late in June. Where there are no fruit-dots the hairs on the upper
surface of the fronds will help to distinguish it from specimens of the
Marsh fern tribe, which it somewhat resembles. The regular rows of nearly
straight, clear-cut sori of the fertile fronds are very attractive, and
the lower ones, as well as those at the slender tips of the pinnae, are
frequently double.

Rich woods and moist, shady banks, New England to Kentucky and westward.
Generally distributed but hardly common.

(4) NARROW-LEAVED SPLEENWORT

ATHYRIUM ANGUSTIFOLIUM. _Asplenium angustifolium_

Fronds one to four feet tall, pinnate. Pinnae numerous, thin, short-stalked,
linear-lanceolate, acuminate, those of the fertile fronds narrower.
Fruit-dots linear. Indusium slightly convex.

[Illustration: Narrow-leaved Spleenwort. _Athyrium angustifolium_ (Vermont)
(Geo. E. Davenport)]

In rich woods from southern Canada and New Hampshire to Minnesota and
southward. September. Not common. Mt. Toby, Mass., Berlin and Meriden,
Conn., and Danville, Vt. Can be cultivated but should not be exposed to
severe weather, as its thin and delicate fronds are easily injured. Woolson
writes of it, "There is nothing in the fern kingdom which looks so cool and
refreshing on a hot day as a mass of this clear-cut, delicately made-up
fern."

[Illustration: Pinnae and Sori of _Athyrium angustifolium_]

HART'S TONGUE

_Scolopendrium_. PHYLLITIS

Sori linear, a row on either side of the midvein, and at right angles to
it, the indusium appearing to be double. (_Scolopendrium_ is the Greek for
centipede, whose feet the sori were thought to resemble. _Phyllitis_ is the
ancient Greek name for a fern.) Only one species in the United States.

[Illustration: Sori of _Scolopendrium vulgare_]

(1) _Scolopendri