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89. ACTINELLA Pers., Nutt. 
Low herbs, with narrow alternate leaves dotted with resinous atoms, 
solitary many-flowered heads terminating scapes or slender naked pe- 
duncles, wedge-oblong 3 toothed yellow pistillate rays, ovate or lanceo- 
late membranaceous or coriaceous nearly equal involueral bracts ap- 
pressed in 2 or 3 rows, hemispherical or conical naked receptacle, top- 
shaped densely silky-villous achenes, and pappus of 5 or more ovate or 
lanceolate very thin chaffy scales, 
* Involucre of numerous distinct not rigid bracts: leaves entire (except in a form of no, 2). 
1. A. linearifolia Torr. & Gray. Annual or biennial, villous or glabrate, 3 dm, 
high or less, simple or branched: leaves linear: peduncles filiform.—In sandy soil, 
throughout southern and western Texas. 
2. A. scaposa Nutt. Perennial, rather sparsely cespitose, the branches of the 
caudex slender and often ascending, with seape-like peduncles, loosely villous and 
glabrate: leaves linear to lanceolate, not rarely laciniate-lobed.—Rocky prairies, 
throughout Texas. Associated with the species is var, LINEARIS Nutt., in which the 
leaves are all narrowly linear and entire and more rigid. 
* * Involucral bracts rigid, in 2 rows, the outer connate at base. 
3. A. Texana Coulter & Rose. A small annual 5 to 15 em. high: leaves mostly 
radical, oblong and tapering at base, entire or few-toothed; those of the stem nar- 
rower and toothed, becoming linear and entire above: heads small, 4 to 6 mm. high, 
with minute rays not projecting beyond the bracts.—Harris County (Thurow) and 
southwestern Texas ( Palmer), 
4, A. odorata Gray. Annual, 3 to6 dm. high, branching, leafy, somewhat floc- 
cose-woolly: heads small and scattered: leaves 1 to 3-pinnately divided, the lobes 
filiform.—Open ground, throughout southern Texas. Called “limonillo” and used 
as a perfume plant (Havard). 
90. HELENIUM L. (SNEEZE-WEED.) 
Erect branching herbs, with alternate (impressed-punctate) leaves 
mostly decurrent on the angled stem and branches which are termi- 
nated by single or corymbed (yellow rarely purple) many-flowered 
heads, wedge-shaped 3 to 5-cleft fertile (rarely sterile) rays, small re- 
flexed linear or awl-shaped involucral bracts, globose or oblon g naked 
receptacle, top-shaped ribbed achenes, and pappus of 5 to 8thin 1-nerved 
chaffy scales, the nerve usually extended into a bristle or point. 
* Rays fertile (rarely sterile, occasionally wanting): scales of pappus not dissected. 
+ Root annual: leaves all filiform-linear, not decurrent on the stem or branches : scales of 
pappus tipped with prominent awn. 
1. H. tenuifolium Nutt. Glabrous, slender, much branched, very leafy up to the 
slender peduncles: leaves mostly entire: rays much surpassing the globular disk: 
pappus scales ovate, abruptly tipped with a longer awn which equals the villous 
achene.—River bottoms, etc., extending from the Gulf and Mississippi States to west- 
ern Texas. Associated with the species in Texas is var. BADIUM Gray, with dull 
purplish brown (instead of yellow) disk, and lower leaves sometimes pinnately 
parted. 
