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minating the branches, sterile rays, convex or conical receptacle with 
chaff either strongly concave or conduplicate and embracing the com- 
monly pubescent achenes, and pappus of 2 chaffy awnsor scales, one to 
each principal angle of the achene (occasionally 1 or 2 more), and of 2 
or more intermediate commonly truncate scales on each side, either per- 
sistent or deciduous. 
1. V. helianthoides HBK. Minutely hispidulous-pubescent or scabrous, green: 
stem 6 to 20dm. high, paniculately branched above: leaves mostly alternate, slender- 
petioled, ovate, acuminate, sometimes very broadly ovate (the larger 10 to 15cm. 
long and 7.5 to 10cm. wide), sometimes ovate-lanceolate, from slightly to coarsely 
serrate: heads paniculate, usually slender-peduncled: involucre only 6mm. high, 
shorter than the strongly convex disk, nearly simple, of subulate or linear bracts: 
chaff somewhat cuspidately mucronate or acuminate: pappus a pair of scales on each 
side between the chaffy awns, erose at the truncate summit.—Shady or more open 
grounds, central and western Texas. 
2. V. cordifolia Gray. Hispid or hispidulous and scabrous: stem rather stout, 
6 to 9 dm. high, leafy to the top, commonly branched above: leaves mostly opposite, 
subcordate-ovate or deltoid, acute, serrate or denticulate, either sessile or short- 
petioled, rough: heads mostly corymbose and short-peduncled: involucre fully 12 
mm. long, equaling the barely convex disk, of lanceolate and acuminate erect bracts 
in 2 or 8 series: chaff gradually acuminate: achenes narrowly cuneate-oblong, 
almost equaled by the chatfy awns, the intermediate scales narrowly oblong and rigid, 
equaling the breadth of the achene.—Near water courses, western Texas, 
V. longipes Coulter is Zecmenia hispida Gray. 
66. HELIANTHUS L. (SUNFLOWER.) 
Coarse and stout herbs, with solitary or corymbed heads, yellow neu- 
tral rays, imbricated herbaceous or foliaceous involucre, flat or convex 
receptacle with persistent chaff embracing the 4-sided and laterally 
compressed smooth achenes (which are neither winged nor margined), 
and a very deciduous pappus of 2 thin chaffy scales on the principal 
angles and sometimes 2 or more small intermediate scales. 
* Annuals: leaves mosily allernate, petiolate: receptacle flat: disk brownish, 
+ Stem erectand commonly robust. 
1. H. argophyllus Torr. & Gray. White with soft and silky wool (sometimes floc- 
ose, and more or less deciduous with age): leaves slightly serrate: otherwise like 
the next.—Apparently confined to Texas, 
2. H. annuus L. (COMMON SUNFLOWER.) ‘Tall and rough: leaves ovate or the 
lower cordate, serrate: involucral bracts broadly ovate to oblong, long-pointed, 
ciliate: disk usually 2.5cem. broad or more. (Incl. 4. lenticularis Dougl.)—Abundant 
in all valleys. ‘‘Seeds used for food by Indians and to fatten poultry by Mexicans, 
yielding by expression a fair quantity of oil” (Havard). 
3. H. petiolaris Nutt. More slender, 3 to 9 dm. high: leaves oblong- or ovate- 
lanceolate, smaller (2.5 to 7.5 cm. long), mostly entire: involucral bracts lanceolate 
or oblong-lanceolate, seldom ciliate: disk 1 em. broad or more.—A species of the 
dry northern plains, extending into the valleys and cafions of southern and western 
Texas. Var. CANESCENS Torr. & Gray, of southwestern Texas, has leaves whitened 
with a fine and close strigulose-sericeous pubescence, the lowest ovate. 
+ + Stems branched from the base, diffuse or decumbent, slender. 
4. H. debilis Nutt. Scabrous to hispid: leaves from ovate to deltoid or even has- 
tate, 2.5 to 7.5 em. long, repand-denticulate to sparingly lobed-dentate, slender- 
