59. PT E ROCAULON. Ell. sk. 2. p. 333 (1824); DC. prodr. 5. p. 453.
Heads many-flowered; the fertile flowers filiform, pistillate, in . several
series; the perfect flowers in the centre (or intermixed with the others, Ell.),
mostly sterile. Scales of the oblong involucre imbricated in several series,
appressed or with slightly squarrose points, caducous. Receptacle minutely
fimbrillate or hirsute. Corolla of the fertile flowers 3-toothed ; the
sterile 5-cleft at the summit. Anthers bicaudate, somewhat exserted. Ache-
nia angled, pubescent with appressed hairs. Pappus of numerous capillary
scabrous equal bristles, longer than the involucre.—Perennial herbs, or
slightly shrubby plants (chiefly natives of tropical America), with a somewhat
tuberous rhizoma. Leaves alternate, lanceolate, entire or denticulate,
very densely tomentose beneath, the margins decurrent along the stem into
continuous foliaceous wings. Heads sessile, densely crowded in simple or
compound spikes. Flowers usually white.
L P ■ pycnostachyum {Ell.): stem herbaceous, simple; leaves lanceolate,
undulate-denticulate, glabrous above ; heads in a dense continuous spike ;
scales of the involucre silky-tomentose, squarrose at the apex.—Ell. 1. c .;
DC .! 1. c. Conyza pycnostachya, Michx.! fl. 2. p. 126 ; Pursh ! Jl. 2. p.
524. Chlsenolobus pycnostachyos, Cass, in diet. sci. nat. 49. p. 348 (1827).
Pluchea pycnostachya, Less. Gnaphalium undulatum, Walt.! Car. p . 203.
Dry sandy soil, S. Carolina! to Florida! May-Aug.—Black Root. (The
root is much used in some parts of the country as an alterative, and as a
cleanser of old ulcers. Elliott.)
60. CALYMMANDRA.
Heads subglobose, subsessile, collected in small axillary clusters, many-
flowered, heterogamous; the flowers all fertile; the pistillate in many series,
in the axils of narrow and plane linear or somewhat spatulate scarious (vil-
lous-lanate) chaff of the receptacle, with a filiform truncate corolla; the perfect
5 in a single central series, each enclosed in an oval convolute woolly
chaff; the short and somewhat inflated minutely 4-toothed corolla more or
less exserted. Scales of the involucre few, similar to and passing into the
chaff. Receptacle conical, punctate. Anthers with very short tails. Branches
of the style short; in the perfect flowers oblong, flat; in the pistillate filiform.
Achenia oval-oblong, nearly terete, very smooth, destitute of pappus,
those of the perfect flowers similar, but enclosed by the subtending chaff.—
A small annual herb, branched from the base, clothed with a very white and
silvery appressed wool; the branches slender, somewhat simple, erect, bearing
small bracteate or irregularly involucrate clusters of few heads, closely sessile
in the axils of linear-oblanceolate or narrowly spatulate entire leaves; the
heads themselves (about a line long) on short pedicels concealed by the wool.
C. Candida.
Texas, Drummond!—Plant 5-10 inches high. Leaves alternate, approximate,
half an inch or more in length, very much longer than the clusters in
their axils. Chaff falling away when the achenia ripen, all nearly equal in
length, scarious, glabrous towards the base, that of the perfect flowers woolly
throughout, somewhat herbaceous, obtuse, shorter than the flowers, but investing
the achenia, just as those of Micropus are enclosed by the scales of
the involucre. In the latter, the exterior and pistillate flowers are thus invested
: in this remarkable genus, on the contrary, the central staminate
(and fertile) flowers are enclosed, to which circumstance the generic name
alludes.
61. FILAGINOPSIS.
Heads subglobose-ovoid, collected in dense umbelliform clusters, many-
flowered; the fertile flowers pistillate, numerous, and in many series in the
axils of the linear-oblong and obtuse (woolly-tipped) flat and scabrous equal
chaff of the receptacle, with a filiform truncate corolla; the 2-5 central staminate,
with a tubular-infundibuliform 4-toothed corolla, sessile and with no
vestige of an ovary, subtended by as many of the chaffy scales of the receptacle,
and nearly equalling them in length. Involucre of few scales entirely
similar to the chaff of the receptacle, and only distinguishable by having
no flowers in their axils : involucrate bracts mostly 5, in a single series, ob-
ovate-spatulate, herbaceous, with Scarious margins, very woolly. Receptacle
flat or somewhat convex, papillose-punctate. Style in the staminate flowers
undivided; in the fertile with short filiform branches. Achenia oval, smooth
and glabrous, slightly obcompre’Ssed (that is parallel with the chaff), entirely
destitute of pappus.—Annual woolly herbs, with the aspect of Filago (natives
of Mexico and Texas), much branched from the base, diffuse. Leaves ob-
long-spatulate, entire, sessile. Heads in involucrate (simple or proliferous)
woolly glomerules, terminating the branches.
This genus differs from Evax in the broad and flat receptacle, obtuse chaff, &c.;
from the Diaperia of Nuttall in the roundish very many-flowered heads, the narrow
chaff numerous in each series, the sessile sterile flowers, &c.
1. F. multicaulis: glomerules often proliferous; chaff of the sterile flowers
linear-spatulate, somewhat herbaceous and woolly throughout, slightly involving
the entirely glabrous corolla.—Evax multicaulis, DC. ! prodr. 5. p.
459. E. verna, Raj.! herb.
Texas, Berlandier / Drummond ! Dr. Leavenworth ! (the former also obtained
it in Mexico.)—Plant 3-6 inches high, with rather slender diffuse stems
and branches, clothed with long loose wool. Leaves one-fourth to half an
inch long ; the involucrate ones unequal and often shorter than the irregular
clusters. Heads ovoid ; the chaff all but the inner series glabrous except at
the summit, where the long wool is densely matted and coherent, while the
base separates from the receptacle when the achenia are mature.
2. F. Drummondii: glomerules seldom proliferous : chaff of the sterile
flowers entirely similar to that of the fertile, or wanting; the corolla (sterile),
like the chaff, clothed with long woolly hairs at the summit.
Texas Drummond !—Plant 4-8 inches high, more loosely branched than
the preceding, which it exceedingly resembles. Heads fewer in a cluster
and rather larger, very many-flowered, hemispherical-obovoid; the oblong-
linear chaff all similar and of the same length, clothed towards the tips with