CARDUACEAE 1431 
78. TITHONIA Desf. Annual, Helianthus-like herbs. Leaves alternate: 
ei bs or three lobed. Heads large, erect, on peduncles swollen just 
belov e involucre. Involucre hemispheric or broadly campanulate: bracts in 
ios series, the other short and appressed, the inner long, appressed at the base 
and somewhat foliaeeous above. Ray flowers several, neutral: ligules yellow, 
showy. Disk flowers perfect: EM yellow, with a short villous tube dilate 
into a long throat: lobes lanceolate. Stigmas slender, hirsute. Achene broad- 
ened upward, flattened, four-angled, wingless 
embraced by the bractlets. Pappus of 2 
awns or scales, caducous or persistent, ac- 
companied several shorter, always per- 
beseent, scabrous or glabrate above, tapering i 
abruptly to a cuneate-winged peti 
uci. braets of two kinds, the Bac pr ovate, striate and appressed, 
usually aeute, the inner long, Wie dens. striate, somewhat d oo above, 
usually obtuse or rounded, appressed at the e, 18-25 mm. d ligules 4-6 
em. 1 i apex: ac s 
Indies. 
LT. diversifolia (Hemsl.) Gray. Plant up 
to 4.5 m. tall, with à branching, woody stem, 
slightly pu ubescent or dA leaf- blades 
ovate 2 outline, 3—5 lobed, r entir n the 
sistent, seales.—F our or five species, native 
of Mex WwW 
upper stem, E ate, pubes AUR ben ath, pu- 
e pubeseent about 6 mm. long.—Pine- 
xieo, Central Ameriea and the West 
ng, t a 
eae roadsides, and about gardens, em Fla. Nat. of Mex. rt eult.— All 
yea 
o 
E 
[e] 
B 
ect 
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etd 
eM 
ps 
Oo 
77. HELIANTHUS L. Annual or perennial, coarse, erect or diffuse 
herbs. Leaves various, the first ones opposite, sooner or later the succeeding 
ones becoming alternate, or in a few species very rarely all alternate: blades 
he 
sometimes with accessory and intermediate scales, the whole pappus readily 
eaducous; each flower subtended by a conduplicate, Aes braetlet on the 
receptaele. Braets of the involucre in 3 or 4 series, green.—About 100 species, 
American.—Sum.-fall, unless otherwise stated.—SUNFLOWERS. 
Disk-corollas with red, purple, or brown lobes. . RUBRI. 
Disk-corollas with yellow lobes. II. FLAVI. 
ae 
Ray-flowers with ligules more than 
. lon 
Leaves more or less pubescent, "but not dencel y white-hairy. 
Blades E the cane leaves of a long-linear type, 2—8 
wi 
Heads ma leaves alternate. 1. H. dious Tonis: 
Head soli tary: leaves opposite. 2. H. heterophyllus. 
1 Contributed by Elba Emanuel Watson. 
