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14. AMPHIACHYRIS Nutt. 
A diffusely much-branched annual, with narrowly linear entire alter- 
nate leaves, heads solitary on the branchlets and radiate, perfect but 
infertile disk-flowers, and pappus of the ray minute and coroniform, of 
the disk-flowers of almost bristle-like scales more or less dilated and 
united at base: otherwise as Gutierrezta. 
1. A. @racunculoides Nutt. Rather low and slender: leaves narrowly linear, 
the upper filiform: disk-flowers 10 to 20, their pappus of 5 to 8 bristle-like scales 
united at base and slightly dilated upward,—Plains of Kansas and Texas, 
15. GRINDELIA Willd. 
Coarse perennial or biennial herbs, with sessile or clasping alternate 
and spinulose-serrate or laciniate rigid leaves, large radiate many-flow- 
ered heads terminating leafy branches, yellow disk and ray (the latter 
pistillate), hemispherical involucre with bracts imbricated in several 
series and with slender more or less spreading green tips, short and 
thick compressed or turgid truncate glabrous achenes, and pappus of 
2 to 8 caducous awns. 
* More or less pubescent. 
1. G. inuloides Willd. Pubescence minute or short: leaves from oblong to lanceo- 
late or almost ovate, serrate down to the partly clasping or broad base with close- 
set and often gland-tipped salient teeth: involucre glabrous, at length squarrose: 
achenes short and turgid, with rounded-truncate summit, smooth or becoming trans- 
versely corky-rugose: awns of pappus 1 to 3.—Common on the plains of Texas. In 
southern Texas is found var, MICROCEPHALA Gray, which is smaller and more branch- 
ing, with heads only halfas large (6 mm, or so in diameter), achenes more commonly 
rugose-thickened. 
** Whole herbage glabrous. 
2. G. squarrosa Dunal. Leaves spatulate to linear-oblong: involucre squarrose: 
achenes not toothed: pappus awns 2 or 3.—Plains and prairies of Texas, said to be 
particularly abundant west of the Pecos. A common Texan form is var. GRANDI- 
FLORA Gray, with larger heads and very numerous rays (2.5 em. long), taller simpler 
stems, and ovate to oblong upper leaves which are more numerously and equally 
serrate either with obtuse or spinulose teeth. 
8 G. lanceolata Nutt. Leaves lanceolate or linear: involucral bracts erect or 
the lower tips spreading: achenes with 1 or 2 short teeth at summit: awns 2,—Prai- 
ries and barrens of ‘Pexas. 
16. HETEROTHECA Cass. 
Characters as in Chrysopsis, but the achenes of the ray thickish or 
triangular, without pappus or obscurely crowned, and those of the disk 
compressed, with a double pappus, the inner of numerous long bristles, 
the outer of many short and stout bristles. 
1. H. subaxillaris Britt. & Rusby. Annual or biennial, 3 to 9 dm, high, bear- 
ing numerous small heads: leaves oval or oblong, the lower with petioles auricled 
at base, the upper mostly subcordate-clasping (H. Lamarckii Cass.)—Sandy or barren 
soil near the coast and throughout central and western Texas. 
