Ferns of various habits, the rootstocks horizontal, often elongated or short and erect; the leaves simple, pinnate, pinnatifid or decompound, coiled at the ends when young. Sporanges borne in clusters (sori) on the lower side or margins of the leaves or their segments, with or without a membranous covering (indusium).

Represented in the region by the following 10 genera.

Rootstock short, thick, erect or oblique; stems 4—10 inches long with a few brown spreading scales near the base; leaves 1—2 feet long, oblong-lanceolate, thrice pinnate, the pinnæ deltoid-lanceolate, the lower ones distant and smaller, pinnules oblong-lanceolate, finely cut-toothed; sori small, rounded and nearly marginal.

On moist banks in the Selkirks, frequent especially in the vicinity of Glacier, where it forms clumps of considerable diameter, up to 7000 feet elevation.

Rootstock slender and creeping; stems 6—9 inches long; leaves triangular, thin, usually longer than broad, 6—9 inches long, 4—6 inches broad, hairy on the veins, especially beneath; pinnæ linear-lanceolate, the lowest pair deflexed and standing forward, segments oblong, obtuse, entire, the basal ones joined to the main rachis; sori small, near the margin.

In moist woods in the Selkirks at the lower elevations, not common.

Rootstock slender, extensively creeping; leaves or short black stipes, broadly triangular 4—8 inches wide, the three primary divisions 1—2 pinnate, segments oblong, obtuse, entire or toothed; sori near the margin.

In moist woods and thickets throughout the region at the lower altitudes, frequently forming beds of considerable size.

Rootstock slender, creeping; stems 9—18 inches long, dark chestnut brown or nearly black, shining, forked into nearly equal branches at the summit; leaves obliquely orbicular in outline, 8—18 inches broad, thin, the pinnæ arising from the branches of the stem, somewhat radiately arranged, the larger ones 6—10 inches long, 1—2 inches broad, pinnules triangular-oblong, or the terminal one fan-shaped, the lower margin entire and slightly curved, the upper cut, bearing the linear-oblong sori.

Sparingly throughout the region in woods or moist shaded situations, among rocks.

Rootstock stout, widely creeping, subterranean; stems hairy, 1—2 feet high, erect, straw-colored or brownish, leaves soft-hairy, especially on the under surface, 2—4 feet long, 1—3 feet wide, ternate, the three branches each bipinnate, the upper pinnules undivided, the lower more or less pinnatifid.

In dry woods, thickets, and open hillsides, throughout the region.

Rootstock stout, short, and chaffy; stems densely tufted, straw-colored, 2—6 inches long, very slender, chaffy below; leaves ovate or ovate-lanceolate in outline, thin, smooth, 2—3 pinnate, the sterile shorter than the fertile, their segments and pinnules crowded, ovate-oblong or obovate, crenate or slightly sharply cut; fertile leaves with linear or linear-oblong segments half an inch long, the margins at first rolled back to the midrib, at maturity expanded and exposing the light brown sporanges.

Forming tufts among rocks throughout the region but most frequent in the Selkirks.

Rootstock slender, creeping, thread-like; stems slender, scattered 2—3 inches long, dark brown; leaves thin, ovate in outline 2—5 inches long, 1—2 inches wide, 2—3 pinnate or pinnatifid above, the fertile taller, with narrower pinnules and segments, pinnæ lanceolate-deltoid, cut to the rachis, in few lobed or entire segments; indusium broad; veins conspicuous.

In crevices of damp or dripping rocks, preferably limestone, in the Rockies up to 7000 feet elevation; not common.

Rootstock creeping, covered with pale rusty-brown scales; stems tufted, wiry, chestnut brown, 2—4 inches long, hairy; leaves oblong-lanceolate in outline 4—9 inches long, gradually attenuate to the apex, twice pinnate; pinnules somewhat distant, lanceolate-deltoid, acute, deeply pinnatifid or incised, more or less covered with stiff hairs and usually somewhat glandular; sori numerous, covered by the infolded ends of the rounded oblong lobes.

On rocks and among broken stones at the lower altitudes of the eastern Rockies; growing in matted masses.

Rootstock stout, creeping, chaffy with brown scales; stems numerous, densely tufted, brownish below, green above; leaves linear-lanceolate, 2—8 inches long, once pinnate, pale green, with 12—20 pairs of ovate or rhomboid, crenate; obtuse, unequal-sided pinnules; sori oblong, numerous, or scattered.

On dry rocks and slides, frequent through the Rockies.

Rootstock creeping, rather slender for the size of the plant; stems tufted, 6—10 inches long; straw-colored, brownish or reddish, with scattered brown scales which are large and numerous at the broadened base; leaves broadly oblong-lanceolate, pinnæ lanceolate, acuminate, 4—8 inches long; pinnules lanceolate, incised or serrate, sori short, the indusia straight or variously curved.

In moist woods and thickets throughout the region but especially in the Selkirks, being a common fern in the woods in the vicinity of Glacier.

Rootstock short, stout, and densely chaffy; stems 1—5 inches long, bearing large dark brown scales, with some smaller ones; leaves rigid, leathery, and evergreen, narrowly lanceolate in outline, once pinnate; pinnæ broadly lanceolate, scythe-shaped, 1—2 inches long, acute or acuminate at the apex, with an ear-like projection on the upper side at the base, and with a nearly straight edge on the lower, densely spiny-toothed; sori large, nearer the margin than the midrib.

In large tufts among rocks throughout the region.

Rootstock stout, ascending, or erect, chaffy; stems 4—6 inches long, very chaffy below; leaves broadly lanceolate, acute or acuminate at the apex, slightly narrowed at the base, 1—3 feet long, rather firm, half evergreen, pinnate or partly 2-pinnate; pinnæ lanceolate, broadest at the base, gradually acuminate, 3—6 inches long, pinnatifid almost to the rachis, or pinnately divided into oblong, smooth lobes; sori large, borne near the margin, more numerous on the lower halves of the segments.

In rocky woods in the Selkirks on the lower slopes of Mt. Macdonald.

Rootstock stout, chaffy; stems 6—18 inches long, bearing large brown scales with dark centres; leaves broadly ovate or triangular-ovate, commonly 3-pinnate; pinnules lanceolate oblong, the lowest often much elongated; sori medium size; indusium smooth.

In moist woods through the Selkirks, probably the most abundant fern in the vicinity of Glacier.

Rootstock short, erect or decumbent, scaly; stems light straw-colored, 2—6 inches long, tufted, copiously scaly throughout, with light brown scales; leaves 1½—2 feet long, rather firm, broadly lanceolate, gradually tapering from near the middle to both ends; pinnæ 2—3 inches long, deeply pinnatifid, gradually shorter to the lowest which are more distant, broadly triangular, and less than an inch long; segments flat, oblong, and nearly entire; rachis straw-colored, densely scaly with light brown scales, nearly to the apex.

In the Selkirks on the moist mountain slopes and rocky ravines at Glacier.

Rootstock short, creeping, and densely chaffy; stems brown, darker at the base, 2—4 inches long, glandular-hairy; leaves mostly glandular-hairy throughout, lanceolate, 6—12 inches long, tapering from about the middle to both ends; pinnæ numerous, oblong-ovate, pinnatifid into oblong-toothed segments; sori nearly marginal.

In crevices in the rocks and among broken stones on slides, throughout the Rockies, up to an elevation of 7000 feet; frequent.

Rootstock short; stems smooth, brownish below. Leaves smooth, 2—10 inches long, lanceolate; pinnæ triangular, oblong, obtuse, pinnatifid, lower ones rounded and somewhat remote from the others; rachis straw-colored; pinnules oblong-ovate, dentate or crenate, the teeth often turned back and covering the submarginal sori.

Among broken stones on the slides near the base of Mt. Stephen in the Rockies.

Rootstock short; stems 4—8 inches long, leaves thin, smooth throughout, oblong-lanceolate, only slightly tapering below, 4—10 inches long; pinnate or 2—3 pinnatifid; pinnæ lanceolate-ovate, irregularly pinnatifid with a broad central space, and bluntly or sharply toothed segments, decurrent along the margined or winged rachis; sori small, half way between the margin and the midrib; indusium narrow, soon withering.

In crevices in rocks and among broken stones throughout the Rockies.

Rootstock slender, widely creeping; stipes 6—9 inches long, slender; leaves deltoid-ovate, 3—4 pinnate, 3—6 inches broad, the lowest pinnæ triangular-lanceolate and much larger, their inferior pinnules 1—1½ inches long, deeply divided into oblong lobes, deeply toothed; sori numerous; indusium acute, soon withering.

On damp mossy banks and rocks throughout the Rockies; not common.