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» * * * Loaves with revolute entire margins, not scabrous, reinless, woolly beneath. 
6. V. Lindheimeri Gray & Engelm. Excessively leafy up to the corymbiform 
cyme, lanose-canescent even to the obtuse and pointless involucral bracts: leaves 
narrowly linear, glabrate and green above: achenes glabrous: pappus purple.— 
Rocky hills and plains of central and western Texas, 
3. STEVIA Cav. 
Herbaceous or shrubby plants, with mostly opposite and 3-nerved 
leaves, small and narrow discoid heads usually crowded in terminal 
naked cymes or fascicles, white or rose-colored perfect flowers, 3 to 5 
flowered cylindrical involucre of 5 or 6mostly equal rather rigid bracts, 
naked receptacle, narrow corolla, linear slender 5-angled achenes, and 
a variable pappus.—Outs have subsessile and fasciculate heads. 
1. S. serrata Cav. Herbaceous, pubescent or somewhat hirsute, leafy up to the 
dense fastigiate clusters of heads: leaves often alternate, subsessile, spatulate-linear 
to oblong-spatulate, irregularly and sometimes coarsely serrate or some entire, 
strongly punctate: flowers white or pale rose; pappus 1 to 5-awned or in some 
flowers reduced to a crown of short obtuse scales. —West of the Pecos. 
2. §. salicifolia Cav. Shrubby, low and nearly glabrous: leaves mostly opposite, 
subsessile, coriaceous, linear or linear-lanceolate, mostly entire (occasionally ser- 
rate), commonly glutinous-lucid: heads in small and rather open fascicles: flowers 
white: pappus 1 to 3-awned, or sometimes of obtuse scales.—Southern border of 
Texas. 
4. TRICHOCORONIS Gray. 
Fibrous-rooted aquatic or paludose herbs, with branching leafy 
pubescent stems creeping at base or spr ‘ding, opposite (or upper alter- 
nate) sessile and partly clasping glabrate leaves, slender-peduncled 
discoid heads terminating the branches, flesh-color or rose purple per- 
fect flowers, many-flowered involucre of 12 to 18 lax and equal bracts, 
naked convex receptacle, abruptly much dilated corolla, 5-angled- 
achenes, and pappus a minute crown of numerous bristles. 
1. T. Wrightii Gray. Stems assurgent: leaves undivided, sparingly serrate, 
12 mm. or more long; the lower opposite and oblong; the upper alternate and cor- 
date-lanceolate: heads diffusely panicled, only 4mm. high and wide: pappus a 
minute but evident crown.—Wet grounds in the prairies of Texas. 
2 T. rivularis Gray. Stems floating (in shallow water rooting), and flowering 
branches emersed and ascending: leaves succulent, mastly opposite, 2.5 to 5 cm, long, 
cuneate-obovate, sparingly incised or palmately 3-lobed, contracted into a narrow 
connate-clasping auriculate base: heads fewer or solitary, 6 to 8 mm. in diameter: 
pappus a minute andevanescent or obscure crown.—Insprings and streamlets, south- 
western Texas. . 
5. MIKANIA Willd. (CLIMBING HEMP-WEED). 
Mostly twining perennials, with opposite commonly heart-shaped and 
petioled leaves, corymbose-panicled flesh-colored perfect flowers, discoid 
4-flowered heads, 4 involucral bracts, naked receptacle, the flowers, 
achenes, ete., as in Kupatorium. 
1. M. scandens Willd. Smooth or nearly so, with high-twining herbaceous 
stems: leaves somewhat triangular, heart-shaped or halberd-form, pointed, toothed 
