C. VISCIDIFLORUS. 181 



about 15, in poorly defined vertical ranks, broadly to linear oblong or lanceolate, acute 

 or obtuse, firmly chartaceous, glabrous or minutely puberulent, the outer ones sometimes 

 with a greenish thickened spot near the apex; flowers about 5; corolla tubular-funnelform, 

 passing gradually from tube to throat, 4.5 to 7 mm. long, glabrous or only viscidulous; 

 lobes 1 to 2 mm. long, erect to recurved-spreading, glabrous; anther-tips lanceolate, acute, 

 about 0.5 mm. long; style-branches short-exserted, the lanceolate acutish appendage one- 

 half to three-fourths as long as the stigmatic portion; achenes narrowed toward the 

 base, 5-angled, 3 to 4 mm. long at maturity, densely to sparsely villous or silky; pappus 

 slightly exceeding the corolla, of comparatively rigid sordid bristles. (Crinitaria tns- 

 cidiflora Hooker, Fl. Bor. Am. 2:24, 1834.) 



Plains and mountains of western North America, on poor soil, North Dakota to New 

 Mexico, eastern California, British Columbia, and Montana. 



SUBSPECIES. 



The specific limits of C. viscidiflorus as here adopted are the same as those set by Gray in 

 1873 (Proc. Am. Acad. 8:645, as Bigelovia douglasi). From this assemblage of forms 

 there have been published from time to time a total of 20 segregates, 16 of which have 

 been accorded specific rank by those who use a narrow species concept. Even after these 

 17 proposals have been reduced to 10 subspecies, it is found that they pass so insensibly 

 from one to another that they can not be satisfactorily defined. It is believed, however, 

 that the following artificial key and the descriptions will enable one to place a majority 

 of the specimens as they come to hand. 



Key to Subspecies of Chrysothamnus viscidifiorus. 



Herbage densely puberulent, especially in the inflorescence, and the leaves 2.5 to 6 mm. 



wide. (Shrub either low or tall.) (a) lanceolatus (p. 181). 



Herbage glabrous or if pubescent the leaves then 2 mm. or less wide. 

 Shrubs low, mostly 1 to 4 dm. high; leaves only 1 to 2 mm. wide. 

 Bracts without distinctly thickened tips. 



Leaves linear, I to 2 mm. wide and the herbage glabrous (6) pumilus (p. 182). 



Leaves linear-filiform and only 1 mm. or less wide or if wider the herbage puberulent. 

 Twigs and leaves densely puberulent. 



Leaves linear-filiform, 1 mm. wide (c) puberulus (p. 182). 



Leaves linear or linear-oblanceolate, 1 to 2 mm. wide (d) humilis (p. 182). 



Twigs and leaves glabrous (e) stenophyltus (p. 183) 



Bracts with a thickened green spot at tip (/) elegaiis (p. 183). 



Shrubs taller, mostly 4 to 24 dm. high; leaves 2 to 10 mm. wide (rarely narrower in 

 typiciis). Herbage glabrous. 

 Bracts thin, without a distinct greenish subapical spot; plants of non-alkaline soils. 



Leaves 1 to 4 mm. wide, 1- to 3-ncrved ig) typicus (p. 183). 



Leaves 4 to 10 mm. wide, 3- or 5-nerved (h) lati/olius (p. 184). 



Bracts thicker (at least the outer ones) with a conspicuous greenish or brownish spot 



near the obtuse summit; plants of alkaline soils (i) linifolius (p. 184). 



5a. Chrysothamnus viscidiflorus lanceolatus (Nuttall). Low or medium-sized 

 shrub, 2 to 5 dm. high or rarely more; leaves broadly linear or linear-lanceolate, abruptly 

 acute, 1.5 to 4 cm. long, 2.5 to 6 mm. wide, 3-nerved or 5-nerved, usually not twisted, 

 bright green, at least the upper ones densely rough-puberulent ; cyme small, compact, its 

 branches densely puberulent; involucre 5 to 6.5 mm. high; bracts oblong, scarcely keeled, 

 rather obtuse, without subapical spot; achenes densely strigose. (C lanceolatus Nuttall, 

 Trans. Am. Phil. Soc. II, 7:324, 1840.) Montana to Colorado, Nevada, Washington, 

 and Idaho. Type locality, in the Rocky Mountains, toward the sources of the Platte. 

 Collections: Helena, Montana, September 16, 1891, Kelsey (UC); Nowood Creek, Big 

 Horn County, Wyoming, Goodding 509 (Or, NY, UC, US) ; Hayden, Routt County, Colo- 

 rado, Goodding 1791 (DS, Gr, NY, UC, US); Mackay, Custer County, Idaho, Nelson and 

 Macbride 1525 (Gr, NY, UC); Castle Gate, Utah, Jones 5486i (US); banks of the Colum- 

 bia River at Grants, Oregon, September 15, 1887, Howell (UC, tall form); Coulee City, 

 Washington, Lake and Hull 7S2 (Gr, tall form). 



