are more or less membranous. (Pellaea, from the Greek
_pellos_, meaning dusky, in allusion to the dark stipes.)

(1) PURPLE CLIFF BRAKE. _Pellaea atropurpurea_

Stipes dark purple or reddish-brown, polished and decidedly hairy and
harsh to the touch, at least on one side. Fronds coriaceous, pale, simply
pinnate, or bipinnate below; the divisions broadly linear or oblong, or
the sterile sometimes oval, chiefly entire, somewhat heart-shaped, or
else truncate at the stalked base. Veins about twice forked. Basal scales
extending into long, slender tips, colorless or yellow.

[Illustration: Purple Cliff Brake. _Pellaea atropurpurea_]

Another name is "the winter brake," as its fronds remain green throughout
the winter, especially in its more southern ranges. It grows on rocky
ledges with a preference for limestone, and often in full sun. In large and
mature fronds its pinnae are apt to be extremely irregular. While its stipes
are purplish, its leaves are bluish-green, and its scales light-brown or
yellow. Strange to say, this brake of the cliffs thrives in cultivation.
Woolson says of it, "This fern is interesting and valuable. It is not only
beautiful in design, but unique in color, a dark blue-green emphasizing
all the varying tints about it--a first-class fern for indoor winter
cultivation. It is a rapid grower, flourishing but a few feet from coal
fire or radiator, in a north or south window. It quickly forgives neglect,
and if allowed to dry up out of doors or indoors, recovers in due time when
put in a moist atmosphere. It makes but one imperative demand, and that is
the privilege of standing still. Overzealous culturists usually like to
turn things around, but revolving cliffs are not in the natural order of
things. The slender black stipes are very susceptible to changes of light
and warped and twisted fronds result."

Dry, calcareous rocks, southern New England and westward. Rare. Var.
_cristata_ has forked pinnae somewhat crowded toward the summit of the
frond. Missouri.

(2) SMOOTH CLIFF BRAKE

_Pellaea glabella. Pellaea atropurpurea_, var. _Bushii_

Naked with a few, scattered, spreading hairs, smooth surface and dark
polished stipes. Rhizome short with membranous, orange or brown scales
having a few bluntish teeth on each edge. Pinnae sub-opposite, divergent,
narrowly oblong, obtuse; base truncate, cordate or clasping, occasionally
auricled; lower pinnae often with orbicular or cordate pinnules. Steril