354 FLORA OF TEXAS. 



scales of the involucre 6-12, oval or obovate, membrana- 

 ceous, white; receptacle naked; corolla slender; achenia 

 toi3-shaped, -i-angled; pajjpus of 10-20 short obtuse thin 

 scales. — Hoary or woolly herbs, with alternate pinnately 

 lobcd or divided leaves; heads corymbed; Jloivers com- 

 monly white. 



H. scABios^us, L'Her. Hoary-tomentose ; stem corym- 

 bosely branched; leaves pinnatifid or the lowest bipinnati- 

 lid, with lanceolate or oblong divisions; scales of the invo- 

 lucre broadly obovate, longer than the disk; pappus 

 minute. Stem 2° high ; leaves at length smoothish above. 



HELEXIUM, L. 



Heads many-flowered, radiate, the rays pistillate, wedge- 

 shaped, 3-5 cleft; scales of the involucre in 2 rows, the 

 outer ones linear or subulate, spreading, the inner fewer 

 and chaffy; receptacle naked, convex, globose, or oblong; 

 corolla of the disk 4-5-toothed; achenia top-shaped, fur- 

 rowed, hairy; pappns of 5-8 membranaceous pointed or 

 awned 1-nerved scales. — Erect branching herbs, with the 

 sthn winged by the alternate decurrent leaves ; heads ter- 

 minating the branches; flowers mostly yellow. 



* Disk globose ; corolla of the disk mostly 5-cieft. 



H. autuzyIXAle, L. Smooth or minutely pubescent; 

 leaves lanceolate or oblong, serrate, strongly decurrent; 

 scales of the involucre linear-subulate ; scales of the papj^us 

 ovate-lanceolate, den ticulate, awn-pointed ; raj/s 3-5 cleft, 

 longer than the disk. Stem'2°-^° liigk; achenia hairy. 



H. TEXUIFOLIUM, Nutt. Smooth; stem slender, very 

 leafy; leaves narrow-linear, entire; heads on long and 

 slender peduncles; scales of the involucre subulate; scales 

 of the pappus ovate, entire, abruptly a^^Tied; achenia villous. 

 Stem l°-2° high; branches erect. 



