THISTLE FAMILY 867 



23. TONESTUS A. Nels. 



Dwarf herbaceous perennials, with woody taproots and short caudices. 

 Leaves spatulate to linear, entire, alternate. Heads solitary, terminal, radiate. 

 Involucres campanulate or hemispheric; bracts loosely imbricate, in 2-3 series, 

 more or less foliaceous, the outer ones often leaf-like. Ray-flowers many, yellow, 

 pistillate. Disk-corollas yellow, somewhat enlarged upwards, deeply 5-toothed. 

 Appendages of the style-branches oblong to subulate. Pappus soft and white. 



Basal leaves oblanceolate, spatulate, or oblong; bracts lanceolate or oblanceolate. 

 Bracts acute; plants glandular or viscid. 



Bracts lacerate or ciliate; stem-leaves linear or linear-lanceolate, long-ciliate. 



1. T. laceratus. 

 Bracts neither lacerate nor ciliate; stem-leaves oblanceolate, not ciliate. 



2. T. Lyallii. 

 Bracts obtuse; plant soft-pubescent or glabrate, scarcely viscid. 3. T. pygmaeus. 



Leaves and bracts linear. 4. T. linearis. 



1. T. laceratus (Henders.) A. Nels. Stem 1 dm. high or less, glandular- 

 puberulent; basal leaves spatulate to narrowly oblanceolate; involucres 1 cm. 

 high and wide; bracts subequal in 2 or 3 series, lanceolate, hyaline-margined; 

 achenes densely sericeous. Aplopappus laceratus Henders. Mountains, among 

 rocks: Ida. Subalp. Alp. Jl. 



2. T. Lyallii (A. Gray) A. Nels. Stem 1 dm. high or less; leaves oblanceo- 

 late or spatulate, or the upper oblong; involucres about 1 cm. high and broad; 

 bracts lanceolate, glandular-puberulent; achenes glabrous or nearly so. A. 

 Lyallii A. Gray. High mountains: Alta. Colo. Ida. Wash. B.C. Mont. 

 Alp. Jl-Au. 



3. T. pygmaeus (T. & G.) A. Nels. Stem 2-5 cm. high; leaves linear- 

 spatulate to spatulate-oblong, 2-4 cm. long; heads 8-10 mm. high; bracts oblong 

 to oval; achenes silky-strigose. Stenotus pygmaeus T. & G. A. pygmaeus A 

 Gray. High mountains: Wyo. N.M. Alp. Subalp. Je-Au. 



4. T. linearis Nels. & Macbr. Stem about 1 dm. long; leaves all narrowly 

 linear, 3-nerved, minutely crisp-pubescent, 2-4 cm. long; bracts about 1 cni. 

 long, with narrow scarious margins, in 2 series; ligules broadly linear; achenes 

 minutely pubescent. Mountains: Ida. 



24. OREOCHRYSUM Rydb. MOUNTAIN GOLD. 



Plants with slender horizontal rootstock, leafy, viscid-puberulent above. In- 

 volucral bracts oblong, pale, rather obscurely 1-ribbed, chartaceous or the outer 

 foliaceous, in about three moderately unequal ranks. Rays several, short. 

 Disk-corollas narrowly trumpet-shaped, deeply 5-toothed. Style-appendages 

 lanceolate, longer than the stigmatic portion. Achenes angled. Pappus white 

 or slightly tawny, of soft scabrous bristles. 



1. O. Parryi (A. Gray) Rydb. Stem 1-4 dm. high, puberulent or somewhat 

 viscid above; basal leaves petioled, 5-15 cm. long; blades spatulate or oblanceo- 

 late, glabrous; stem-leaves oval to oblong, sessile; heads 10-12 mm. high; ligules 

 5-6 mm. long, pale yellow, 1 mm. wide; achenes glabrous. Aplopappus Parryi 

 A. Gray. Mountains: Wyo. N.M. Ariz. Utah; Mex. Submont. Subalp. 

 Jl-S. 



25. SOLIDAGO L. GOLDENROD. 



Perennial caulescent herbs, mostly with rootstocks (all ours), rarely shrubby 

 at the base. Leaves alternate, often toothed. Heads small, several-flowered, 

 paniculate or thyrsoid, radiate. Involucres campanulate, turbinate, or cylin- 

 dric; bracts in several series, well imbricate, ribless; receptacle small, alveolate. 

 Ray-flowers pistillate; ligules yellow, short. Disk-flowers hermaphrodite, fer- 

 tile; corolla usually yellow, tubular to narrowly campanulate, 5-lobed. Anthers 

 obtuse at the base. Style-branches flattened; appendages lanceolate. Achenes 

 terete, usually ribbed. Pappus of many rough hair-like bristles, in 1-2 series. 



Leaves glabrous or slightly pubescent along the veins and on the margins. 



Leaves not triple- veined; branches of the inflorescence not recurved-spreading; heads 

 not secund. 



