219 
++ ++ Leaves narrow, chiefly alternate, not 3-nerved, scabrous both sides: heads rather 
small; bracts loose attenuate. 
12. H. grosse-serratus Martens. . Stem smooth and glaucous, 18 to 30 dm. high: 
leaves elongated-lanceolate or ovate-lanceolate, taper-pointed, sharply serrate or 
denticulate, acute or attenuate at base, petioled, often whiter and finely pubescent 
beneath: involucral bracts lance-awl-shaped, slightly ciliate-—Extending from the 
dry plains of the north into Texas. Var. HYPOLEUCUS Gray is a Texan form with 
leaves almost silvery-canescent with fine and dense soft tomentum, the larger with 
either cuneate or truncate base. 
13. H. giganteus L. Stem hairy or rough, 9 to 30 din. high, branched above: leaves 
lanceolate, pointed, minutely serrate or nearly entire, green both sides, narrowed and 
ciliate at base, but nearly sessile: involucral bracts long, linear-lanceolate, pointed, 
hairy or strongly ciliate,—Moist or wet ground of the northern and Gulf States, and 
reported from Gillespie County, Texas. 
14. H. Maximiliani Schrad. Resembling the last; stout, often simple, 3 to 30 
din. high: leaves becoming rigid and very scabrous, entire or sparingly denticulate: 
heads rather large, usually short-peduncled, terminal and in the upper axils; bracts 
longer attenuate and more rigid.—Extending from the northern prairies into Texas, 
++ ++ ++ Leaves all or most of them opposite, 3-nerved. 
15. H. hirsutus Raf. Stem simple or forked above, stout, 3 to 12 dm. high, bristly- 
hairy: leaves all shortly petioled, ovate, lanceolate, gradually pointed, slightly ser- 
rate, rounded or obtuse at base, very rough above, usually rough-hairy beneath: 
involucral bracts ovate-lanceolate, pointed: rays about 12.—Extending from the 
northern States into Texas. Var. STENOPHYLLUS Torr. & Gray is a small form of 
Louisiana and Texas, with narrow lanceolate leaves almost sessile by a somewhat 
contracted base. 
67. FLOURENSIA DC. 
Almost glabrous resiniferous-viscid much branched shrub, with al- 
ternate entire leaves, corymbed or paniculate short-peduncled heads 
from the upper axils, whitish or yellowish rayless heads, flat receptacle 
with scarious chaff conduplicate around the compressed callous-mar- 
gined very villous achenes, and a nearly persistent pappus of a subu- 
late awn from each angle of the truncate summit, and commonly some 
intermediate smaller ones or scales. 
1. F.cernua DC. Very branching and leafy, with the aromatic bitterness and 
odor of hops, 9 to 18 dm. high: leaves obovate and oblong, acute at both ends, ob- 
scurely veiny: heads seldom over 1 cm. high, subsessile in the axils or terminating 
paniculate branchlets, soon nodding: involucral bracts lanceolate and erect, with 
some outer and spreading foliaceous ones passing into leaves.—Dry hills and plains of 
western Texas. 
68. ENCELIA Adans. 
Ours are herbs, with opposite or alternate broad usually serrate leaves, 
rather showy radiate heads (rays mostly yellow and neutral) on naked 
peduncles, soft or mainly scarious chaff, wingless emarginate or truncate 
mostly naked achenes, and pappus none or an awn or its rudiment at 
each margin. 
* Root annual: petioles all naked at base: some uppermost leaves alternate. 
1. E. exaristata Gray. Stem rather slender, minutely puberulent or sparsely vil- 
lous, naked at summit and bearing loosely paniculate heads: leaves ovate and oblong- 
ovate, barely serrate, rarely somewhat incised, on narrowly margined petioles: outer 
