Corolla ovate and urn-shaped, with a short revolute 5-toothed limb.
A small depressed shrubby evergreen, much branched and tufted, smooth, with coriaceous opposite elliptical leaves, on short petioles, with revolute margins.
Filaments slender, united in a ring at the base; anthers oblong, revoluteafter flowering.
Fertile fronds shorter, pinnate with margins of the pinnæ revolute into a necklace form containing the sori.
Notholàena Small ferns with fruit-dots borne beneath therevolute margin of the pinnules, at first roundish, but soon confluent into a narrow band without indusium.
The less revolute margins of the fertile frond, the simple veins, its thinner texture, and its more distant fruit-dots aid in its identification.
From the New York Fern it may be distinguished easily by the somewhat abrupt instead of tapering base of the frond, by the strongly revolute margins of the fertile frond, and by its long stalk.
Illustration: PLATE XXVI MARSH FERN Fertile frond Sterile frond] From the Massachusetts Fern it may be distinguished by its forked veins, the less revolute margins of the fertile frond, and by its thicker texture and deeper green.
A leaf with revolutemargins has the edges rolled under, as in the Andromeda polifilia.
Note: A revolute leaf is coiled downwards, with the lower surface inside the coil.
These should also be so far revolute that the side view should exhibit a perfect semicircle in its outline, and the eye or prolific disc, in the centre should be entirely concealed.
Broadly funnel-form, with six deciduous segments; at lengthrevolute to the stem.
Campanulate; three or four lines long; with five revolute lobes; having a small scale at base, opposite each lobe.
