LOASA FAMILY 135 



1. Mentzelia laevicaulis (Dougl.) Torr. & Gray. Blazing Star. Fig. 3280. 



Bartonia laevicaulis Dougl. ex Hook. Fl. Bor. Amer. 1: 221. pi. 69. 1834. 

 Mentzelia laevicaulis Torr. & Gray, Fl. N. Amer. 1: 535. 1840. 

 Touterea laevicaulis Rydb. Bull. Torrey Club 30: 276. 1903. 

 Nuttallia laevicaulis Greene, Leaflets Bot. Obs. 1: 210. 1906. 



Perennial, the stems stout, erect, 3-10 dm. high, branched above. Leaves lanceolate, sinuate- 

 toothed, 5-15 cm. long, canescent with short appressed hairs ; flowers sessile on short branches, 

 diurnal; bracts linear-subulate, irregularly toothed, long-acuminate; sepals lanceolate, _ 2-4 cm. 

 long, reflexed in fruit ; petals 5, or sometimes apparently 10 on account of the 5 petaloid stami- 

 nodia, yellow, oblong-lanceolate, 5-8 cm. long ; stamens numerous, in several series ; capsule 

 cylindric, 3 cm. long; seeds winged, minutely tuberculate. 



Gravelly or sandy plains and washes. Arid Transition and Upper Sonoran Zones; eastern Washington and 

 Montana south to Utah, Nevada, and southern California. Type locality: "on the gravelly islands and rocky 

 shores of the Columbia near the Great Falls." June-Sept. 



2. Mentzelia Brandegei S. Wats. Brandegee's Stick-leaf. Fig. 3281. 



Mentzelia Brandegei S. Wats. Proc. Amer. Acad. 20: 367. 1885. 

 Touterea Brandegei Rydb. Bull. Torrey Club 30: 276. 1903. 

 Nuttallia Brandegei Greene, Leaflets Bot. Obs. 1: 210. 1906. 



Perennial or biennial, from a simple root, stems erect, branched, 2-3 dm. high, scabrous. 

 Leaves linear-lanceolate, 2-5 cm. long, the lower petioled, the upper sessile, sinuate-pinnatifid 

 with linear lobes, scabrous on both surfaces ; flowers corymbose, sessile, 1-3, terminating the 

 branches ; bracts narrow, usually entire ; sepals 3-4 cm. long, densely pubescent ; petals 5, yellow, 

 15-20 mm. long, lanceolate, acuminate, pilose ; stamens 20-35, the outer 5 petaloid and alter- 

 nating with the petals; capsule narrowly oblong-cylindric, 15-20 mm. long; seeds narrowly 

 winged. 



Sandy soils, Arid Transition and Upper Sonoran Zones; eastern British Columbia south to Yakima County, 

 Washington. Type locality: "Near the Simcoe Mountains on the mesa bordering Satus Creek." June-Aug. 



3. Mentzelia puberula Darlington. Darlington's Stick-leaf. Fig. 3282. 



Mentzelia puberula Darlington, Ann. Mo. Bot. Gard. 21: 177. 1934. 

 Mentzelia Peirsonii Jepson, Fl. Calif. 2: 529. 1936. 



Perennial, 15-25 cm. high, the stems widely branching from the base, white, short-hirsute. 

 Basal leaves broadly oblanceolate, narrowed to a slender petiole, the upper sessile, oblong-oval 

 to ovate, irregularly dentate, grayed with a dense scabrous puberulence ; flowers terminating the 

 numerous branches, pedicellate ; bracts narrowly linear-lanceolate ; sepals narrowly lanceolate, 

 revolute, 6-8 mm. long ; petals 5, narrowly obovate, 8-10 mm. long, rounded at apex, distinctly 

 clawed at base ; 5 outer filaments spatulate, rounded or slightly notched at apex, antheriferous, the 

 inner linear ; capsule turbinate-campanulate, scabrous ; seeds broadly winged, faintly punctate. 



Desert ranges, Sonoran Zones; eastern Mojave Desert and Colorado Desert, California, to western Arizona 

 and northern Lower California. Type locality: Kane Springs, Ord Mountains, San Bernardino County, Cali- 

 fornia. Feb.-April. 



4. Mentzelia oreophila Darlington. Argus Stick-leaf. Fig. 3283. 



Mentzelia oreophila Darlington, Ann. Mo. Bot. Gard. 21: 175. 1934. 



Perennial from a stout lignescent root, the stems 1-2 dm. high, scabrous becoming smooth 

 and white. Leaves few, sessile, lanceolate to ovate-lanceolate, attenuate at base, 2-6 cm. long, 

 the upper smaller, irregularly sinuate-dentate, scabrous, the pale green epidermis evident be- 

 tween the short whitish hairs ; flowers borne on the ends of the branches ; bracts linear ; sepals 

 ovate-lanceolate, 9-11 mm. long, reflexed in fruit; petals 5. narrowly obovate, 10-12 mm. long, 

 yellow, glabrous ; outer filaments dilated, rounded or slightly notched at the apex ; capsule 

 oblong-ovoid, 8-10 mm. long, pedicelled, short-hirsute; seeds numerous, broadly winged and 

 minutely punctate. 



Rocky mountain slopes, Sonoran Zones; desert ranges of Inyo and eastern San Bernardino Counties, Cali- 

 fornia, and adjacent Nevada and Arizona. Type locality: Argus Mountains, altitude 5,000 feet, Inyo County, 

 California. This species is closely related to Mentzelia leucophylla Brandg. of Nevada, but that has the leaves 

 thicker with strongly revolute margins and whitish gray with a dense covering of short stiff hairs. April-June. 



5. Mentzelia multiflora (Nutt.) A. Gray. Yerba Amarilla. Fig. 3284. 



Bartonia multiflora Nutt. Proc. Acad. Phila. 4: 23. 1848. 

 Mentzelia multiflora A. Gray, Mem. Amer. Acad. 4: 48. 1849. 

 Nuttallia multiflora Greene, Leaflets Bot. Obs. 1: 210. 1906. 

 Mentzelia longiloba Darlington, Ann. Mo. Bot. Gard. 21: 176. 1934. 



Perennial from a stout taproot, the stems 4-8 dm. high, corymbosely branched, often smooth 

 below, barbellate-pubescent above. Leaves linear-lanceolate, 2-8 cm. long, sessile, sinuate- 

 dentate, scabrous on both surfaces with stiff barbate hairs; bracts linear, revolute; sepals sub- 

 ulate, 7-10 mm. long, spreading or reflexed in fruit; petals 10, oblong-obovate, rounded or obtuse 

 at the apex, 15-20 mm. long; stamens numerous, filaments of the outer slightly dilated; capsule 

 15-20 mm. long, broadly oblong ; seeds light brown, flat with broad wings. 



Dry sandy plains, Sonoran Zones; Invo Countv, California, to Colorado, and south to western Texas, Sonora, 

 and Lower California. Type locality: "Sandy hills along the borders of the Rio del Norte, Santa Fe," New 

 Mexico. April-Sept. 



