Bigdovia. COMPOSITE. 137 



tains in Colorado to the borders of New Mexico and Utah; first coll. by Parry. Forms 

 approach B. graceolens. 



* * Style-appendages short-=ubulate, these and the deltoid-ovate obtuse anther-tips hardly ex- 

 serted:- akciies linear-oblong, glabrous: involucre campanulate-cylindraceous, equalling the 

 15 to 20 flowers: herbage glabrous throughout. 



B. Engelmanni, GRAY. A span or two high, in tufts from a snffrutescent subterranean 

 branching caudex or rootstock : stems simple, very leafy up to the cymose-glomerate heads : 

 leaves all narrowly linear (inch or two long, only a line wide), rigid: heads (few or rather 

 numerous in the cluster) barely half-inch long : bracts of the involucre firm-chartaceous, 

 oblong or innermost lanceolate, regularly imbricated and appressed, outer similar but short, 

 all abruptly mncronate or short-cuspidate, slightly greenish below the tip. Proc. Am. 

 Acad. xi. 75. Plains of Colorado at Hugo Station, Engelmann, Parry, Patterson. 



2. CHRYSOTH^MNUS, Gray, 1. c. Heads narrow or small. 5-flowered (in 

 B. Douglasii sometimes 6-7-flowered), mostly numerous and crowded : involucre 

 (anomalous first species excepted) of dry and chartaceous more or less carinate 

 bracts imbricated so as to form 5 conspicuous vertical ranks (less manifestly so 

 when the bracts are less numerous): corollas narrow: style-appendages with 

 exserted subulate- or setaceous-filiform appendages : akenes slender : fruticose or 

 suffruticose and branching, with entire narrow leaves. Bigelovia, 2, DC. 1. c. 

 Chrysothamnus, Nutt. Trans. Am. Phil. Soc. 1. c. 



* Transition to preceding section : involucral bracts comparatively large, not carinate nor obviously 

 5-stichous, some outer ones foliaceous-acuminate or appendaged : anther-tips very short and 

 obtuse: corollas said to be even "white." 



B. albida, M. E. JONES. Shrubby, a foot or two high, more or less resinous-viscid, fasti- 

 giately branched, very leafy: leaves all filiform, rnucronate, not obviously punctate: heads 

 fastigiate-glomerate at the summit of the branchlets, 5 or 6 lines long : involucre oblong- 

 turbiuate or cylindraceous ; its bracts rather few and coriaceo-chartaceous, lanceolate ; outer 

 with rather rigid subulate-acuminate and recurved or spreading foliaceous tip or appendage : 

 inner wholly chartaceous and pointless: corollas probably ochroleucous ; lobes of the deeply 

 cleft limb linear-lanceolate: akeues pubescent. Gray, Proc. Am. Acad. xvii. 209. Arid 

 districts, east of the Sierra Nevada: Owens Valley, California, coll. 1875, Kellogg. Wells 

 Station, W. Nevada, Marcus E. Jones, who states that the flowers are white. 



* * Genuine species, with thinner more chartaceous and carinate involucral bracts, none folia- 

 ceons-tipped : anther-tips lanceolate or narrowly oblong. 



-t Akenes and ovaries glabrous, 4-6-a-ngled and with broad epigynous disk: pappus rigidulous: 

 corollas 5-toothed or short-lobed: bracts of the involucre acute or acuminate, numerous and 

 strictly 5-stichous, 5 or 6 in each vertical rank: herbage not punctate, slightly or not at all bal- 

 samic-resinous: heads half to three-fourths inch long, somewhat fastigiately glomerate. 



B. depressa, GRAY, 1. c. Obscurely scabro-puberulent and pale, a span or two high from a 

 decumbent woody base : branches leafy up to the gloinerule or fasciculate cyme of few 

 heads : leaves short (about half-inch or less long), lanceolate or lowest rather spatulate, rigid, 

 mucronate-acute, with carinate midrib and no veins : heads half-inch long : involucral bracts 

 lanceolate, gradually acuminate into an almost setaceous tip. Ckrysotharrinus depresses, 

 Nutt. PI. Gamb. 171. Linosyris depressa, Torr. in Sitgreaves Rep. 161.-- Plains of S. Colo- 

 rado to adjacent New Mexico and S. Utah ; first coll. by Gambel. 



B. pulchella, GRAY, 1. c. Glabrous and green, shrubby, 2 or 3 feet high, fastigiately much 

 branched, very leafy up to fastigiate-cymose heads : leaves narrowly linear, plane (inch or 

 less long), rather obtuse, with ciliolate-scabrous margins and midrib not prominent : heads 

 two-thirds to three-fourths inch long : involucral bracts rigid-chartaceous and lower ones ob- 

 scurely herbaceous on the back, much carinate, acute and cuspidate-mucronate. Linosyris 

 pulchella, Gray, PI. Wright, i. 96 ; Torr. in Sitgreaves, 1. c. t. 4. W. borders of Texas to 

 adjacent New Mexico and Colorado ; first coll. by Wright. 



B. Bigelovii, GRAY, 1. c. Canescent with fine close tomentum when young, glabrate, 

 shrubby, a foot to a yard high, fastigiately much branched, rigid : branches less leafy, bear- 

 ing a few fastigiate-clustered heads (these half to two-thirds inch high) : leaves nearly fili- 



