1300 CARDUACEAE 
equal, in one or two series. Receptacle flat, naked, fimbrillate or pubescent. Ray-flowers 
pistillate, fruit-producing: ligules yellow. Disk-flowers perfect, fruit-producing : corollas 
tubular. Anthers sometimes slightly sagittate. Achenes narrow, more or less pubescent, 
5~10-ribbed. Pappus a single series of scabrous or barbellate firm bristles. 
1. Arnica acaülis (Walt.) B.S.P. Foliage hirsute. Stems 2-10 dm. tall, simple 
or sparingly branched above, commonly bearing 1 or 2 pairs of leaves with nearly oblong 
blades: leaves mainly basal; blades spreading on the ground, oblong to oval or ovate, 5- 
12 em. long, shallowly toothed or nearly entire, sessile : heads showy, long-peduncled : 
involucral bracts linear or linear-lanceolate, about 1 cm. long, acute: ligules of the ray- 
flowers deep yellow, 1.5-2.5 em. long: achenes 4 mm. long. (A. nudicaulis Nutt. ] 
In pine lands and open woods, Pennsylvania to Florida. Spring. LEOPARD'S-BANE. 
139. BRECHTITES Raf. 
Annual caulescent normally coarse herbs. Leaves alternate: blades flat, not rigid, 
usually toothed or pinnatifid. Heads heterogamous, discoid, in corymbs or panicled 
corymbs. Involucres narrow, somewhat swollen at the base : bracts mostly in 1 series, nar- 
row, the main series sometimes accompanied by smaller ones. Receptacle flat or concave, 
naked. Pistillate flowers marginal. Perfect flowers central, like the pistillate, fruit-pro- 
ducing. Corollas tubular, white or greenish. Anthers obtuse at the base. Achenes nar- 
row, angled or striate. Pappus copious, conspicuous, of soft white elongated bristles. 
1. Erechtites hieracifdlia (L.) Raf. Foliage glabrous or sparingly hirsute. Stems 
2-20 dm. tall, simple or much branched : leaf-blades flimsy, spatulate-oblong or lanceolate, 
5-20 em. long, acute or acuminate, coarsely toothed, incised or pinnatifid, the lower ones 
with winged petioles, the upper sessile and partly clasping: heads not showy : involucres 
cylindric, 12-15 mm. long ; bracts narrowly linear : achenes 1.5 mm. long, ribbed : pappus 
bright white, silky. 
In open woods, and especially on burnt soil, Newfoundland to the Northwest Territory, Florida, 
Louisiana and Mexico. Summer and fall. FIRE-WEED. 
140. MESADENIA Raf. 
Perennial herbs, with mostly glabrous foliage and sometimes a milky sap. Stems 
corymbosely branched above. Leaves alternate: blades various, sometimes ample, undu- 
late or toothed, commonly petioled. Heads often numerous, discoid, corymbose. In- 
volucres cylindric or nearly so: bracts narrow, about 5 in 1 series, but commonly accom- 
panied by a few small ones at the base of the involucre. Receptacle flat, with a fleshy 
projection at the center, not chaffy. Corollas tubular, white, pinkish or yellowish : lobes 
usually with a midnerve. Anthers not tailed at the base. Achenes narrow, 5-11-ribbed. 
Pappus copious, of soft scabrous white bristles. INDIAN PLANTAIN. 
Bracts of the involucre wingless. 
Corolla-lobes fully twice as long as the throat. 
Leaf-blades pedately or digitately veined, those of the lower leaves broader than long. 
Leaves green on both sides or glaucous beneath ; blades;pedately veined. ; x 
Leaves green : stem furrowed. 1. M. reniformis. 
Leaves glaucous beneath. P 
Stem furrowed. 2. M.similis. | 
Stem terete. 3. M. atriplicifolia. 
Leaves glaucous on both sides: blades digitately veined.’ 4. M. maxima. 
Leaf-blades parallel-veined or subpinnately veined : stem terete. 
Leaf-blades ovate, commonly broadly so. 5. M. ovata. 
Leaf-blades linear to lanceolate. 6. M. lanceolata. 
Corolla-lobes but slightly longer than the throat. 7. M. diversifolia. 
Bracts of the involucre winged along the midrib. ; 
Stems terete, merely striate: blades of the upper stem-leaves hastate. 8. M. difformis. 
Stems channeled or angled: blades of the upper stem-leaves not hastate. 
Lower leaves with 7-9-veined entire or crenate|blades. 
Leaf-blades entire or nearly so. 9. M. tuberosa. 
Leaf-blades crenate. 10. M. Floridana. 
Lower leaves with 3-5-veined sinuate-dentate blades. 11. M. sulcata. 
1. Mesadenia renifórmis (Muhl.) Raf. Stems 1-3 m. tall, sometimes tomentulose 
above, angled: leaf-blades ample, reniform, 1-6 dm. broad, repand or angulately lobed, 
deeply cordate to cuneately truncate, green : heads often numerous : involucral bracts often 
5, oblong to lanceolate, 8-11 mm. long: corollas with lobes fully twice as long as the 
throat : achenes 5 mm. long, black. 
In rich woods, New Jersey to Minnesota, Georgia and Tennessee. Summer and fall. 
1 Prepared with the assistance of Mr. Roland M. Harper. 
