* Segtnmts o f the fron d smooth or slightly hairy.
2. C. W r ig h tii, Hook. Fronds 2 to 3 inches long, ovate-oblong, smooth, herbaceous,
pinnate; pinnss about five pairs, deltoid-ovate, bipinnatifid; segments oblong, incised ; involucres
herbaceous, terminal on the ultimate segments!—Vol. IL , t. Ivii., p. 85—.Western Texas
to Arizona.
3. C- v i o ida, Davenport. Fronds 3 to 5 inches long, oblong-lanceolate, herbaceous,
viscid and minutely glandular, pinnate ; pinniB S to 6 pairs, deltoid, bipinnatifid; _ involucres
herbaceous, terminal on the ultimate segments.— Vol. I., t. xii., p. 85.— Caliiornia.
4. O. A la b am sn s is , Kunze. Fronds 2 to 8 inches long, chartaceous, smooth, lanceolate,
bipinnate ; pimim numerous, oblong-lanceolate ; pinnules triaugular-oblong, rather acute,
often aiiriculate or lobed j involucres pale, rather broad, sub-coriaceous..— Vol.- II., t. Ivii.,
p. 89.— Virginia to Alabama and Texas.
5. C. m ic ro p h y lla , Swartz. Fronds 4 to 10 inches long, chartaceous; sparingly
pubescent beneath, oblong-lanceolate or somewhat pyramidal, bipinnate ; pinnules ovate-
ob ong, obtuse, entire or pinnately incised, involucres narrow, scarcely different from the
texture of the úond, interrupted or ,sub-continuous.— Vol. IL , t. Ivii., p. Si..— Florida and
New Mexico.
* * Segments decidedly hairy or glandular, but not tomentose.
6. C. v e s t it a , Swartz. Fronds 5 to 12 inches long; herbaceous, hirsute with articulated
and pointed rusty hairs, oblong-lanceolate, bipinnate; pinnules oblong-ovate, obtuse, toothed
or incised, the ends of the lobes reflcxed and forming herbaceous involucres.— Vol. I., t.
ii., p. 13 .—New York to Georgia and westward to Kansas.
7. C. C o o p e r s , Eaton. Fronds 3 to 8 inches long, herbaceous, hirsute with articulated'
and often gland-bearing viscid hairs, ovate-lanceolate, bipinnate; pinnules roundish-ovate,
crenate and incised ; involucres herbaceous, formed of the ends of the lobes.—Vol. I., t. ii.,
p. 7 .— C alifornia.
8. C. leu cop od a , Link. Fronds 3 to 4 inches long and broad, broadly deltoid or
pentagonal, viscidly puberulent, 3-4-pinnate ; pinnules ovate, obtuse, divided into rounded
lobules which are reflexed to form herbaceous involucres.— Vol. I I . , V. x lix ., p. 2 9 .—
Western Texas.
§ 3 . P h y s a p t e r i s . Involucres continuous around the greater p a rt o f the margin of
the very tniuuic and bead-like ultimate segments; fronds 2-4,-pinnate, the lower surface
tomentose or scaly.
* Fronds tomentose beneath, but not scaly.
Upper surface smooth.
9. C. g ra c illim a , Eaton. Fronds mostly 2 to 4 inches long, linear-oblong, bipinnate
or partly tripinnate ; pinnules crowded, oblong-oval, about one line long, very woolly
beneath; involucres yellowish-brown, rather broad,.—Vol. IL , t. Ixxix., p. 247. — Oregon
and California.
4- -i- Upper surface pubescent or somewhat tome>ilosa.
— Fronds only 2 to ^ luches long.
10 . C- lan u g in o s a , Nutt.' Frond ovate-lanceolate, tripinnate or bipinnate with
pinnatifid pinnules; ultimate segments less than a line long; upper surface scantily tomentose,
the lower surface matted with jointed woolly hairs ; involucres herbaceous, very narrow.
Vol. L, t. vi., p. 4 1 .— R ocky Mts. of British America to Illinois and Arizona.
— = Fronds \ to 12 inches long, or longer.
1 1 . 0 . tom en tosa, Link. Stalks hairy ; fronds 8 to 15 inches long, oblong-lanceolate,
both surfaces webby-tomentose with whitish hairs, tripinnate ; ultimate segments roundish
obovate, 1-2 to 3-4 of a line long; involucres whitish, continuous round the segment.—
Vol. I . , t. xlv., p. 345.— Virginia to Missouri and Texas.
12 . C. B a to n i, Baker. Stalks with narrow scales as well as hairs ; fronds 4 to 9
inches long, oblong-lanceolate, above woolly-pubescent, beneath matted-tomentose and partly
scaly, tripinnate ; ultimate segments half a line long, rounded-obovate ; margins continuously
recurved, the edge membranaceous. Vol. I., t. x lv ., p. 349.— Colorado to Arizona.
* • Fronds very tomentose beneath, the tonientum mixed with ciliated scales.
13 . C. L in d h e im e ri, Hook. Root-stock slender, creeping; fronds 3 to 5 inches long,
above whitish tomentose, beneath covered with ciliate scales passing into tomentura, 3 -4
pinnate ; ultimate segments 1-4 o f a fine long, very densely crowded; involucre very narrow,
herbaceous.— V o l. I I ., t. Ixxiv., p. 2 1 3 .— Texas to Arizona.
* * * Fronds very scaly beneaih, lomentum scanty or none.
Scales nearly entire; root-stock slender.
14. C. F e n d le r i, Hook. Scales of root-stock loose, nerveless ; frond 3 to 6 inches
long, tripinnate; ultimate pinnules rounded and entire or obovate and 2 -3 lobed ; scales
broadly ovate, acuminate, sometimes sparingly ciliate at the base.— Vol. I I ., t. Ixxix., p.
2 4 1.— Colorado to Arizona.
-1- -i- Scales conspicuously ciliated.
15 . C. m y i’io p h y lla , Desv. Root-stock short, often nodose, covered with strongly
nerved sc a le s; fronds 3 to 8 inches long, 3 -4 pinnate; ultimate segments roundish or
roundish-obovate, sometimes 3-Iobed, covered beneath with ovate ciliated scales, and sometimes
more or less hairy on one or both surfaces.— Vol. II., t. Ixxix., p. 243.—Western
Texas to California.
16. O. C le v e lan d ii, Eaton. Root-stock cord-like, covered with strongly nerved scales;
fronds 4 to 6 inches long, 3 -4 pinnate, covered beneath with fulvous-brown closely imbricated
elegantly ciliated scales ; upper surface smooth; ultimate segments roundish.— Vol. I ., t.
xii., p. 89.—Southern California.
§ 4. A l e u r it o p t e r i s . Involucres various, confluent 0
with white or yellow powder.
• distinct ; frcmds covered beneath
17 . O. a rg é n te a , Hook. Fronds i to 4 inches long, deltoid-ovate, pedately tripartite
with pinnatifid divisions, the lobes entire or crenately lobed ; powder varying from white to
yellow; involucres scarious.— Vo l. IL , t, xlix., p. 3 1 .—Alaska.
7. P E L LÆ A , L ink.
§ I . C h e ilo p le c to n . FrOTtds herbaceous or sub-coriaceous ; veins clearly visible ; involucre
broad a7id usually covering the sporangia till they are fu lly ripe.
1 . p. B r sw e r i , Eaton. Root-stock short, densely covered with narrow fulvous chaff;
fronds membranaceous, 2 to 6 inches long, simply pinnate with mostly unequally 2-lobed
pmnæ.— Vol. I . , t.xiiii, p. 3 3 1 .— California to Utah and Colorado.
2. P . g r a c il is , Hook. Root-stock very slender, creeping, nearly naked ; fronds very
delicate, 2 to 4 inches long, oblong-ovate, pinnate with a few once or twice pinnatifid
pinnæ; segments oblong or obovate ; involucres broad and delicate.— Vol. I I . , t. liv., p. 65.
—Labrador to Colorado.