190. LYGODESMIA. Don, in Edinb. phil.jour. 6. p. 305 (excl. spec.);
Hook.fl. Bor-Am. l .p . 295; DC.
Lygodesmia 6c Erythremia, Nutt.
Heads 5-10-flowered. Involucre elongated cylindrical, of 5-8 linear scales
in a single series, and calyculate with a few very short imbricated bracteolate
scales. Receptacle scrobiculate. Branches of the style much exserted.
Achenia linear, elongated, somewhat cylindrical, striate, smooth, not contracted
at the apex. Pappus of very copious and scarcely scabrous whitish capillary
bristles, in many series, rather persistent.—Perennial glabrous and somewhat
glaucous rigid branching herbs (natives of sterile plains chiefly beyond
the Mississippi), with the habit of Chondrilla: the leaves linear or subulate,
entire; those of the branchlets reduced to mere scales. Root perpendicular.
Heads solitary terminating the stem or branches, erect. Flowers reddish-
purple or rose-color.
This genus differs from Prenanthes and Nabalus rather in its striking habit than
in any marked or important floral characters.
§ 1 . Heads 5-flowered: pappus soft: stems very much branched, not spines-
cenl.—E u l y g o d e sm ia .
1. L . juncea (Don! 1. c.) : stems very much branched, striate; lower
linear-sublanceolate, rigid; the upper subulate.—Hook. ! fl. Bor.-Am. 1.
p . 295, t. 103 ; DC. prodr. 7. p . 198. Prenanthes juncea, Pursh ! Jl. 2.
p . 498; Nutt. ! gen. 2. p . 123.
Plains of the Missouri and Platte to the Rocky Mountains, Lewis1 Nut-
ta ll! Dr. James ! Lieut. Fremont! and of the Saskatchawan, Drummond!
May-June.—About a foot high. Lower leaves 1-2 inches long. Flowers
purple according to Pursh, rose-color according to Nuttall, blue according to
Hooker. Pappus extremely copious, at first nearly white; the soft slender
bristles scarcely at all scabrous. Mature achenia slender, half an inch
!0Dg-
§ 2. Heads A-h-flowered: pappus rather rig id : stems divaricately much
branched: the branchlets spinescent.—P l e ia c a n t h u s , Nutt.
2. L. spinosa (Nutt.): stem and branches not striate, rigid; lower leaves
linear, thickish; those of the branches reduced to minute bracts; proper
scales of the rather short cylindraceous involucre about 4, lanceolate; the
calyculate scales conspicuous, ovate.—Nutt.! in trans. Amer. phil. soc.
(n. ser.) 7. p . 444.
Plains of the Rocky Mountains towards California, Nuttall!—A span to a
foot high, divaricate and spreading; “ the base somewhat pubescent, and
producing remarkably large tufts of brownish matted down.” Nutt.
Flowers rose-red. Pappus less copious and more rigid than in the preceding,
by no means barbellate, as described by Nuttall, but appearing very slightly
scabrous under a good lens. Mature achenia not seen.
§ 3. Heads about 10-flowered: pappus rather soft: stems scapiform, sparingly
branched: leaves mostly radical, linear and elongated, somewhat fleshy.
—E rythremia, Nutt.
3. L. grandiflora: dwarf; stems several from the same root (a span
high), scarcely longer than the narrowly linear radical leaves.—Erythremia
grandiflora, Nutt. ! in trans. Amer. phil. soc. 1. c. p. 445.
Borders of the Platte, near the Rocky Mountains, Nuttall!—Heads large
for the size of the plant, equalling those of the following species. Proper
scales of the involucre about 8; the calyculate scales ovate, ciliate. Ligules
large and showy, rose-red. Achenia unknown. Pappus somewhat evidently
denticulate-scabrous towards the base.
4. L. aphylla (DC. 1. c .): stem slender, elongated, striate-angled, spar-
ingly dichotomous towards the summit, many times longer than the attenuated
linear-filiform chiefly radical leaves ; bracts minute at the origin of the
branches.—Prenanthes pumila, Baldwin! mss. P. aphylla, Nutt.! gen. 2.
p. 123, if in Sill. jour. p. 299 ; Ell. ! sk. 2. p . 261. Erythremia aphylla
Nutt. ! 1. c. p . 446.
/3. Texana: stem stouter; leaves flatfish, sparingly and remotely pin-
natifid-laciniate. (Perhaps a distinct species.)
Pine barrens, St. Mary’s, Georgia, Baldwin! Florida, Mr. Croom! Dr.
Chapman ! Dr. Leavenworth ! &c. {3. Texas, Drummond !—Stem about 2
feet high, nearly naked. Heads showy; the cylindrical involucre nearly an
inch long: the calyculate scales very small, ciliate. Ligules large, rose-
color. Achenia very long and slender. Pappus slightly fawn-colored
scarcely scabrous.
191. MALACOTHRIX. DC. prodr. 7. p. 192. (char, imperfect.)
Malacomeris, Leucoseris, & Leptoseris, Nutt.
Heads many-flowered. Involucre broadly campanulate or hemispherical;
the scales narrow, numerous, more or less imbricated in 2-3 series, the exterior
often calyculate. Receptacle naked. Ligules narrow. Achenia oblong,
truncate at both ends, angled or nearly terete, 8-15-striate or ribbed, smooth,
glabrous ; the summit furnished (as in Andryala and many Hieracia) with a
minute or inconspicuous crenulate or many-toothed ring, surrounding the
base of the true pappus. Pappus consisting of a single series of slender and
rather soft silvery-white capillary bristles (20-40 in number), which are serrulate
scabrous towards the apex, but minutely and sparsely barbellate near
the base, deciduous.—Californian herbs (with a single and dubious exception),
of somewhat varied aspect, mostly with a deciduous pubescence, and
pinnatifid or undivided leaves. Flowers yellow or white.
This genus is most allied to Andryala; with which the section Leucoseris nearly
agrees in habit, and from which the naked receptacle, the different pubescence, &c.
chiefly distinguish it.
§ 1 . Annual, acaulescent: scales o f the involucre narrowly linear, acuminate,
in 2-3 series; the exterior shorter and loose : flowers yellow.—E u m a l a c o -
thrix.
1 . M. Californica (DC.! 1. c .) : softly and loosely villous when young, at