This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Polypodium fragrans L. Sp. PI. 1089. 1753.
Dryopteris fragrans Schott, Gen. Fil. 1834.
Rootstock stout, erect, densely chaffy with brown shining scales. Stipes 2'-4' long, chaffy; blades lanceolate to narrowly oblanceolate, 3'-12' long, firm, aromatic, nearly or quite 2-pinnate, the apex acute; pinnae numerous, 1/2'-1 1/4' long, oblong-lanceolate to deltoid-lanceolate, usually subacute; segments oblong, obtuse, adnate, de-current, deeply incised to subentire, nearly covered by the sori; indusium thin, very large, nearly orbicular, long-persistent, its margin ragged and sparingly glandular, the sinus narrow.
Polypodium cristatum L. Sp. PI. 1090. 1753. Aspidium cristatum Sw. Schrad. Journ. Bot. 18002: 37.
1801. Dryopteris cristata A. Gray, Man. 631. 1848.
Rootstock stout, creeping, densely chaffy. Sterile leaves low, short-stipitate, spreading, much shorter than the fertile, evergreen. Fertile leaves rigidly erect, 1 1/2°-3 1/2° long, long-stipitate, withering; blades 1°-2 1/2° long, 3'-6' broad, linear-oblong to lanceolate, acuminate, deeply bipinnatifid, dark green; pinnae spaced, oblong-lanceolate to triangular-ovate or the lower ones subtriangular; deeply pinnatifid into 6-10 pairs of oblong to triangular-oblong, obtuse, finely serrate segments, the basal ones more deeply cut; sori nearly medial; indusia large, orbicular-reniform, glabrous.
In wet woods and swamps, Newfoundland to Saskatchewan, south to Virginia, Kentucky. Arkansas, Nebraska and Idaho. Ascends to 2700 ft. in Maryland. Also in Europe and Asia. July-Aug. Crested-fern or crested wood-fern.
Aspidium cristatum var. Clintonianum D. C. Eaton in Gray,
Man. ed. 5, 665. 1867. Dryopteris cristata var. Clintoniana Underw. Native Ferns, ed.
4, 115. 1893. Dryopteris Clintoniana Dowell, Proc. Staten Id. Assoc. Arts & Sc. 1: 64. 1906.
Rootstocks stout, creeping, densely chaffy. Leaves 2 1/2°-4 1/2º high; stipes 1° or more long, straw-colored or brownish, with thin concolorous or often dark-centered scales; blades 1 1/2°-3° long, 5'-10' broad, oblong to.ovate-oblong, acute or acuminate, deeply bipinnatifid; pinnae apart, oblong-lanceolate, broadest at the base, or lower ones unequally elongate-triangular, deeply pinnatifid; segments oblong, usually obtuse, serrate, or the basal ones pinnately cut; sori 3-7 pairs, borne near the midvein; indusia orbicular-reniform, glabrous.
In swampy woods, Maine and Ontario to Wisconsin, and North Carolina. Often confused with the preceding and the following species.