g92 CARDUACEAE 



Plant 2-3 dm high: leaves linear, 1-2 cm. long. 1. /. stenomeres. 



PlSt less than 2dm. high; leaves oblong or lanceolate, 5-10 mm. long. 



1. I. stenomeres (A. Gray) Greene. Stems erect, canescent or glabrate; 

 leaves acute, mucronate, scabrous-pubenilent; involucres hemispheric, 10-12 

 mm high, 15-20 mm. broad; bracts linear, acute or acuminate, puberulent in 2 

 series, slightly unequal; ligules pale violet, 10-12 mm. long; outer pappus setu- 

 lose. ' Aster stenomeres A. Gray. Mountain slopes: Mont. Ida. Wash. B.C. 

 Submont. Je-Jl. 



2. I. alpina (Nutt.) Greene. Stems 1-2 dm. high, canescent, simple; leaves 

 5-12 mm. long, rigid, scabrous-puberulent; involucres hemispheric, 8-10 mm. 

 high 12-15 mm. broad; bracts in 3 series, linear-lanceolate, puberulent, acumi- 

 nate'; ligules about 1 cm. long, light violet; outer pappus sometimes distinctly 

 squamellate. Chrysopsis alpina Nutt. Aster scop ulorum A. Gray. Mountains: 

 Mont. Wyo. Nev. Ore. Submont. My-Jl. 



43. LEUCELENE Greene. HEATH ASTER. 



Suffruticose perennials, diffusely branched. Leaves oblanceolate, linear, or 

 subulate. Heads solitary at the ends of the branches. Involucres turbinate; 

 bracts imbricate in several series, herbaceous with narrow scarrous margins. 

 Ray-flowers pistillate and fertile; ligules white, turning reddish. Disk-flowers 

 perfect, white; corollas tubular-funnelform. Style-branches with ovate obtuse 

 appendages. Achenes long and slender. Pappus of long slender white bristles. 



Upper leaves strigose, slightly glandular and not conspicuously hispid-ciliate. 



Lower leaves broadly spatulate, upper linear-subulate; branches long and slender. 



1. L. arenosa. 



Leaves all linear-spatulate, or the upper linear; branches short. 2. L. serotina. 



Upper leaves conspicuously hispid-ciliate, copiously glandular. 



Upper leaves linear-oblanceolate, the lower spatulate. 3. L. hirtella. 



Upper leaves linear-subulate, the lower linear or linear-oblanceolate. 



Leaves of the branches 6-12 mm. long. 4. L. alsinoides. 



Leaves of the branches 2-5 mm. long. 5. L. ericoides. 



1. L. arenosa Heller. Stems 1-3 dm. high, strigose, branched; lower leaves 

 petioled, hispid, 1-1.5 cm. long; upper leaves 5-8 mm. long; involucres 6-7 mm. 

 high and broad; bracts linear-lanceolate, hirsute, scarious-margined ; ligules 3 

 mm. long. Dry hills: Tex. Colo. Ariz.; Mex. Son. Submont. 



2. L. serotina (Greene) Rydb. Stems erect, 1 dm. high or less; leaves 5-10 

 mm. long, strigose, or the lower hirsute-ciliate, scarcely glandular; involucres 

 5-6 mm. high; ligules about 3 mm. long. L. ericoides serotina Greene. Arid 

 hills: Tex. Colo. Utah Ariz. Son. Je-Au. 



3. L. hirtella (A. Gray) Rydb. Stems 1 dm. high or less, decidedly glandu- 

 lar-puberulent; lower leaves about 1 cm. long; all leaves hispid-ciliate; involucres 

 5-6 mm. high and fully as broad; bracts linear-lanceolate, more or less glandular- 

 puberulent, acute, scarious-margined; ligules 3-5 mm. long. Diplopappus ericoides 

 hirtella A. Gray. Dry hills: Tex. Wyo. Utah Ariz. Son. Submont. Ap-Jl. 



4. L. alsinoides Greene. Stems about 1 dm. high, strigose; lower leaves 

 about 1 cm. long, the upper bristle-tipped and appressed; involucres 5-6 mm. high 

 and broad; bracts strigose, slightly glandular-puberulent; ligules 5 mm. long. 

 Dry hills: Tex. Kans. Colo. N.M. Plain Submont. Ap-Je. 



5. L. ericoides (Torr.) Greene. Stems 1-1.5 dm. high; lower leaves about 

 1 cm. long; involucres barely 5 mm. high and broad; bracts less imbricate than 

 in the other species, strigose; ligules white, 5 mm. long. Inula ericoides Torr. 

 A. ericaefolius Rothrock. Plains: Kans. Tex. Colo. Plain. S. 



44. MACHAERANTHERA Nees. TANSY ASTER, VISCID ASTER. 



Annual, biennial, or short-lived perennial, leafy, caulescent herbs, with tap- 

 roots, never with rootstocks. Leaves alternate, bristle-tipped, pinnatifid, ser- 

 rate, or rarely entire, the teeth or lobes bristle-tipped. Heads corymbose or 

 paniculate, radiate. Involucres hemispheric or turbinate; bracts with narrow 



