Part 1, 1914] CARDUACEAE : HELENIEAE 71 



involucre 12-13 mm. high, 10-15 mm. broad; bracts floccose when young, linear, a few of 



the outer ones with spreading or recurved tips, acute; corollas white or flesh-colored, decidedly 



pubescent, about 10 mm. long, the marginal ones not much larger than the central ones; 



anthers included; achenes 5-6 mm.; squamellae 4, linear-oblong, about half as long as the 



corolla, and 2-4 outer oblong cuneate much smaller ones. 



Type locality: Foothills, western Nevada. 



Distribution: Utah, Arizona, Nevada, and eastern California. 



Illustration: S. Wats. Bot. King's Expl. pi. 18, f. 1-5. 



21. Chaenactis brachiata Greene, Leaflets 2: 224. 1912. 



A short-lived perennial; stem 2-4 dm. high; leaves mostly at the base of the stem, 3-4 



cm. long; blades obovate or broadly oval, pinnatifid into 15-19, approximate, spreading 



divisions, again pinnatifid or toothed, white-tomentose ; stem-leaves few and somewhat smaller; 



heads 3-6, corymbose; lateral peduncles 5-10 cm. long, usually spreading at the base and 



curved upwards with erect heads; involucre turbinate, about 12 mm. high, 12-15 mm. broad, 



viscid-hirsute; bracts linear, acute or the outer obtuse; corollas dull- white, 6-7 mm. long, 



puberulent; achenes 7 mm. long, puberulent; squamellae 8, oblong, unequal, obtuse, 3-4 mm. 



long. 



Type locality: Springdale, Utah. 

 Distribution: Utah. 



22. Chaenactis achilleaefolia H. & A. Bot. Beech. Voy. 354. 1838. 



Macrocarphus achilleaefolius Nutt. Trans. Am. Phil. Soc. II. 7: 376. 1841. 

 Chaenactis Douglasii achilleaefolia A. Nelson; Coult. & Nels. Man. 557. 1909. 

 Chaenactis angustifolia Greene, Leaflets 2: 223. 1912. 



A low perennial with a tap-root; stem 1-2 dm. high, rarely 2.5 dm. high, permanently 

 white-tomentose, almost villous, few-leaved, with 1-3 heads; leaves mostly lanceolate in out- 

 line, 2-5 cm. long, permanently white-tomentose, pinnatifid with oblong or obovate, lobed 

 short divisions; peduncles 1-2 cm. long; involucre 7-9 mm. high, 8-10 cm. broad; bracts 

 linear, obtuse, glandular-puberulent, when young floccose; corollas flesh-colored, 5-6 mm. 

 long, puberulent; achenes 5-5.5 mm. long, hirsute; squamellae about 8, linear, unequal, 

 obtuse, 3-5 mm. long. 



Type locality: Plains of the Snake Country, Idaho. 

 Distribution: Wyoming to Oregon and Nevada. 

 Illustration: Stansb. Expl. Utah Bot. pi. 6. 



23. Chaenactis imbricata Greene, Leaflets 2: 222. 1912. 



A perennial, fruticulose and branched at the base; stems strict, about 3 dm. high, leafy, 

 terete, floccose; leaves ascending, 5-10 cm. long, lanceolate in outline, with 9-21 again pin- 

 natifid or toothed narrow divisions, yellowish and loosely but rather densely floccose; heads 

 several in a rather narrow leafy inflorescence; peduncles 2-5 cm. long; involucre broad, some- 

 what turbinate-campanulate, 10-12 mm. high, 12-15 mm. broad, viscid-pubescent; bracts 

 linear, obtuse; corollas flesh-colored or white, 6-7 mm. long, puberulent; achenes 6 mm. long, 

 hirsutulous; squamellae about 8, oblong, obtuse, 4-5 mm. long. 



Type locality: Wenatche Flats, Washington. 

 Distribution: Washington, Oregon, and Idaho. 



24. Chaenactis cheilanthoides Greene, Leaflets 2: 225. 1912. 



A perennial or biennial with a taproot; stem about 3 dm. high, tomentose; leaves 4-8 cm. 



long, rather permanently white villous-tomentose, lanceolate in outline, interruptedly pinnate, 



the larger divisions again pinnatifid, with short oblong divisions; heads several, corymbose; 



involucre about 8 mm. high and 10 mm. broad, floccose and glandular-puberulent; bracts 



linear or somewhat narrowly linear-spatulate, obtuse; corollas whitish, 6 mm. long, puberulent; 



achenes 5-6 mm. long, hirsute; squamellae about 8, linear, 5-6 mm. long, or those of the 



marginal flowers 2-4 mm. long. 



Type locality: Fayette River, Idaho. 

 Distribution: Idaho, Oregon, and Washington. 



