48 



NORTH AMERICAN FLORA 



[Volume 34 



Plant densely and permanently white-tomen- 

 tose. 

 Stem usually less than 3 dm. high; heads few. 



Stem sparingly grayish-tomentose, glabrate in 



age; achenes loosely villous. 

 Stem permanently white-tomentose, densely 

 villous at the base; achenes silky. 

 Pappus minute, hidden by the long hairs of the achenes. 

 Leaves glabrate in age; ultimate segments 5-30 



mm. long; stem 3 dm. high or more. 

 Leaves permanently white-tomentose; ultimate 

 segments short, 1-5 mm. long; stem 1—2 dm. long. 

 Corolla-throat deeply campanulate, 3-4 times as long as 

 the short teeth. 

 Pappus decidedly shorter than the corolla-tube. 

 Stem leafy, densely woolly at the base. 



Leaf-segments rather soft, narrowly filiform; 



pappus-squamellae, 1 mm. long. 

 Leaf -segments broader and stiiTer, nearly 1 mm. 

 wide; pappus-squamellae minute, almost 

 hidden by the hairs. 

 Stem less leafy, subscapose, not densely woolly at 

 the base; leaf-segments broader, stiff, 1 mm. 

 broad. 

 Pappus about equaling the corolla-tube. 



Stem decidedly leafy, densely white-tomentose. 

 Stem more or less scapiform, loosely floccose or 

 glabrate; stem-leaves usually much reduced. 

 Involucre hemispheric, or in H. lugens some- 

 what turbinate, 6-9 mm. high, 9-15 mm. 

 broad. 

 Stem about 3 dm. high; throat of the corolla 

 tapering at the base. 

 Bracts oblong, only the outer purple- 

 margined. 

 Bracts broadly obovate. 



Bracts all more or less rose- or 



purple-tinged. 

 Bracts all yellow-tinged. 

 Stem 1-1.5 dm. high; corolla-throat rounded 

 and swollen at the base; bracts obovate, 

 slightly rose-tinged. 

 Involucre turbinate, about 5 mm. high and 

 broad; plant 1-2 dm. high; margins of the 

 bracts yellow. 

 Leaves simple or simply pinnate with comparatively broad, 

 linear, oblong, or lanceolate divisions and broad rachis; 

 achenes sparingly puberulent or glabrate and indistinctly 

 striate on the faces; squamellae minute or wanting. 

 Leaves thin, all entire or some with 3, rarely 5, lanceolate 



lobes. 

 Leaves firm, all except the earlier and those of the inflor- 

 escence pinnately cleft into 5-9 oblong lobes. 

 Bracts broadly obovate, rounded at the apex, shorter 



than the disk-flowers. 

 Bracts elliptic, acute, as long as the disk -flowers. 

 Heads radiate ; ligules white. 



11. H. tomentosus. 



12. H. cinereus. 



13. H. arenosus. 



14. H. filif alius. 



15. H. luleus. 



16. H. eriopodus. 



17. H. columbianus. 



18. H. macroglottis. 



19. H. niveus. 



20. H. lugens. 



21. H. gloriosus. 



22. H. scaposus. 



23. H. nanus. 



24. H. parvulus. 



25. H. integer. 



26. H . mexicanus. 



27. H. petaloideus. 



28. H. radiatus. 



1. Hymenopappus glandulosus (S. Wats.) Rydberg. 



Hymenolhrix glandulosa S. Wats. Proc. Am. Acad. 23: 278. 1888. 



A leafy-stemmed biennial; stem 5-7 dm. high, more or less purple-tinged, glandtUar- 



hirsute throughout, branched; leaves twice or thrice pinnate, 5-10 cm. long, glandular-hirsute; 



divisions linear, obtuse; heads corymbose on short peduncles; involucre hemispheric, 6-7 mm. 



high, about 1 cm. broad; corollas light-yellow; tube strongly glandular; lobes lanceolate, 



fully as long as the broadly campanulate throat; achenes 3 mm. long, hispidulous on the 



sharp angles, puberulent on the faintly nerved faces; squamellae about half as long as the 



corolla-tube, blunt, unequal, some of them usually with an excurrent midvein. 



Type locality: Sierra Madre, Chihuahua. 

 Distribution: Chihuahua. 



