Flora of the Palousc Region 195 



purplish: akene linear, transversely rugose, hirsute, 5 mm. long: pappus of 

 3-5 rigid lanceolate scales nearly as long as the akenes. In sandy soil on 

 the bluffs of Snake River. 



326. CHAENACTIS. 



Annual, biennial or perennial herbs: leaves alternate, 1-3-pin- 

 nately dissected: heads medium or large, peduncled, terminating the 

 branches: ray-flowers none; flowers yellow, white or flesh-colored, 

 all perfect and tubular but an outer series more or less enlarged 

 simulating rays: involucre campanulate or hemispherical; bracts 

 equal, in 1-2 rows: pappus of 4-12 awnless and nearly or quite 

 nerveless hyaline or chaffy scales: akenes slender, linear, taper- 

 ing to the base, more or less 4-angled. 



C. doug'lasii Hook. & Arn. Perennial, loosely white-tomentose through- 

 out, erect, 30-50 cm. high, branched above: leaves oblong-lanceolate in out- 

 line, 5-10 cm. long, bipinuately parted into numerous rather crowded ob- 

 tuse segments: heads corymbed: involucre campanulate or turbinate, viscid- 

 pubescent, 10-12 mm. high: bracts linear, obtuse: flowers all alike, cream- 

 colored or pinkish: akenes pubescent, those of the rays often glandular: 

 pappus of S-12 large obtuse silvery scales, two-thirds as long as the akenes 

 or in the ray-flowers only one-third as long. Bluffs of Snake River. 



327. HELENIUM. 



Erect, simple or branching herbs: leaves all alternate and all but 

 the lower sessile: heads small or large, many-flowered, on naked 

 terminal peduncles: ray-flowers yellow, several or numerous, pis- 

 tillate; disk-flowers yellow or turning brownish or purplish, small 

 and very numerous, all fertile: involucral bracts spreading or re- 

 flexed at maturity: pappus of 5-12 thin or hyaline chaffy scales 

 with or without midribs: akenes top-shaped, striate-ribbed, hairy 

 on the ribs. 



H. autumnale L- Perennial, erect, 30-90 cm. high, glabrous or puberu- 

 lent: leaves oblong or ovate-lanceolate, acute, dentate or nearly entire, 5-12 

 cm. long, decurrent on the stem forming wings: heads few or many, long- 

 peduncled, 1-1.5 cm. broad: involucre nearly flat, the bracts linear or linear- 

 spatulate, pubescent: rays 10-16, yellow, somewhat drooping, 1-2 cm. long, 

 all fertile: akenes pubescent: pappus scarious, the scales acuminate, awn- 

 pointed. Ranks of Snake River, rare. 



328. GAIIXARDIA. 



Pubescent herbs: leaves alternate, entire or incised or even 

 pinnatifid: heads solitary and long-peduncled, large: ray-flowers 

 yellow or partly dark-purple, sterile: disk-flowers usually purp- 

 lish or brownish: involucral-bracts in 2-3 series, the outer larger 

 and foliaceous: receptacle convex or hemispherical with one or 

 more awns among the flowers resembling chaff: pappus of 6-10 



