Fronds one to four feet tall, pinnate. Pinnæ 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: Pinnæ and Sori of _Athyrium angustifolium_]