COMPOSITAE (COMPOSITE FAMILY) 557 



2. Bahia neo-mexicana Gray, Proc. Am. Acad. 19: 27. 1883. Stems 1-2.5 

 dm. high, minutely puberulent : leaves 3-7-parted into narrow linear divisions ; 

 the uppermost little shorter than the slender peduncles: involucre of about 10 

 sparingly pubescent spatulate bracts: disk-corollas small, with glandular 

 tube, almost equaled by the obovate scales of the pappus, which are much 

 thickened at and near the base. New Mexico and southern Colorado. 



3. Bahia dissecta (Gray) Brit. Trans. N. Y. Acad. Sci. 8: 68. 1889. Stems 

 stoutish, 3-10 dm. high, puberulent or glabrous below, above with the flower- 

 ing branches and short peduncles glandular-pubescent and viscid: leaves 

 1-3-ternately divided or parted; the lobes from oblong and obtuse to nearly 

 linear: heads 10-14 mm. high and broad; bracts of the involucre 16-20, 

 crowded, oblong-lanceolate to obovate-oblong, most of them conspicuously 

 acuminate. B. chrysanthemoides. Along water courses; Wyoming to New 

 Mexico and Arizona. 



69. CHAENACTIS DC. 



Herbs with alternate mostly pinnately dissected leaves, pedunculate soli- 

 tary or cymose heads of yellow or (in ours) white or flesh-colored flowers, and 

 pappus mostly of entire or merely erose persistent scales (in ours 4-14). Re- 

 ceptacle flat. Heads rayless but the marginal flowers enlarged. Achenes 

 slender, linear-tetragonal or more compressed, pubescent. 



Annual 1. C. stevioides. 



Perennials. 



Heads corymbose, short-peduncled; pappus-scales 8-14 . . . 2. C. Douglasii. 



Heads solitary; pappus-scales 4-6 3. C. alpina. 



1 . Chaenactis stevioides H. & A. Bot. Beech. 353. 1840. Floccose-tomentose, 

 glabrate in age, 2-3 dm. high, freely and loosely branched, bearing numerous 

 somewhat cymosely disposed heads on short, slender peduncles: leaves 1-2- 

 pinnately parted into short, linear lobes, uppermost rarely entire: bracts of 

 involucre narrowly linear, obtuse, with obscure midrib: marginal corollas 

 with moderately ampliate unequally 5-lobed limb, not surpassing the disk: 

 scales of the pappus scarcely thickened at base, those of the inner flowers 

 oblong-lanceolate and shorter than the corolla, of the outer one ovate or ob- 

 long, often unequal, sometimes much shorter. Arid areas of our range, and 

 westward. 



2. Chaenactis Douglasii H. & A. 1. c. Canescent with a fine, somewhat 

 floccose tomentum, or sometimes glabrate, 1-4 dm. or more high: leaves 

 mostly of broad outline and bipinnately parted into crowded, short, and very 

 obtuse divisions and lobes: heads 12-18 mm. long, in larger plants several 

 or numerous and corymbosely cymose: scales of the pappus from linear-ligulate 

 to narrowly oblong and one half to three fourths the length of the corolla. 

 From Montana to New Mexico and westward. 



2a. Chaenactis Douglasii achilleaefolia (H. & A.) A. Nels. Dwarf, the 

 leaves more rosulate-tufted and their divisions crowded-approximate. (C. 

 achilleaefolia H. & A. 1. c.). In arid sterile soils; Wyoming to Montana and 

 Washington. 



3. Chaenactis alpina (Gray) Jones, Proc. Cal. Acad. II. 5: 699. 1895. 

 Dwarf, 6-16 cm. high, consisting of a rosette or thick tuft of leaves with very 

 approximate divisions, and naked or scapiform stems, bearing mostly solitary 

 heads, surmounting the subterranean branches of a multicipital perennial 

 caudex or rootstock: heads large, with broadly linear, rough, greenish bracts: 

 pappus scales narrowly oblong, usually 6, 2 of which are somewhat shorter 

 and narrower. C. Douglasii alpina. (C. pedicularia Greene, Pitt. 4: 98. 

 1899). In the mountains of Colorado. 



70. HULSEA T. & G. 



Herbs, viscid-pubescent and balsamic-scented, most of the species when 

 young floccose-woolly, with alternate, mostly sessile, entire or dentate or 



