176 University of California Puhlicatimis in Botany [Vol. 7 



18. Chrysothamnus nauseosus vniv pinifolius (Greene) comb. nov. 



Clirijsolliamnus pinlfulius Grccue, I'itt., vol. 5, p. GO, 1902. 



Slirub of medium size, with slender, very leafy stems: leaves linear- 

 filiform, 1 mm. or less wide, 1-nerved, green to grayish puberulent, 

 often densely toniciilulose beneath: infloreseenee a thyrsoid i)ani('le of 

 roundi'd or pyramidal outline, varying to sliort-oblong : involucre 

 about 7 mm. long, glabrous : corolla 6 to 9 mm. long ; lobes 0.5 to 1 mm. 

 long. 



•o* 



Most abundant in Colorado but extending into adjacent states ; 

 replaced further west by co^isimiUs. The characters separating this 

 variety from graveolens seem to be correlated with the more vigorous 

 growth of the latter and intermediate forms are common. C. patens 

 Rydb., Bull. Torrey Club, vol. 31, p. 652, 1904, is a form of pini- 

 folius with spreading and more or less falcate leaves, but this character 

 is widely variable on single plants and moreover it does not vary in 

 unison with otlier characters. The corolla-lobes in pinifolius are 

 described as about 0.5 mm. long; those of patens as about 1 mm. long. 

 However the lobes are not infrequently as much as 1 mm. long and 

 occasionally even 1.4 nnn. in plants otherwise typical of pinifolius. 

 C. con finis Greene, Pitt., vol. 5, p. 62, 1902, of New Mexico, is scarcely 

 separable from pinifolius. Its best characters lie in the rather obtuse 

 and short-ciliate bracts, but even in pinifolius at least a portion of 

 the bracts aire more or less ciliate. C. falcatvs Greene, I.e., based 

 upon specimens collected on the plains about Grand Junction, Colo- 

 rado, is pinifolius witli the lower face of the leaves white-tomentose, 

 as is commonly the case. Dr. Greene used also the curvature of the 

 leaves and the angle made by them with the stem as differentiating 

 criteria but field studies made by the author at Grand Junction 

 indicate that such characters are much too variable, even in individual 

 plants, to be of use. This is indicated by sheets nos. 203083 and 

 203177 at the Universitj- of California, under graveolens. 



10. Chrysothamnus nauseosus \;\r. consimilis (Greene) comb. nov. 



Chrysothamnus consimilis Greene, Pitt., vol. 5, p. fiO, 1902. 



Shrub of medium or large size, the slender erect twigs very leafy: 

 leaves a.scending or spreading, nearly filiform, less than 1 mm. wide, 

 l-ncT'ved. somewhat resinous and eaneseently tomentulose to neai'ly 

 glabrous: inflorescence an elongated ]iyramidial or cylindrie thyrsus: 

 involucre 7 to mostly 8 or 9 mm. high; bracts not in distinct vertical 

 rows, glabrous: corolla 7.3 to 8.3 mm. long; lobes 1 to 2 nun. long, 

 spreading in age. 



