38 POLYGONACEAE 



2 mm. long, glabrous or somewhat villous-pubescent on the margins ; involucres sessile and mostly 

 solitary at the nodes, narrowly turbinate, 2.5-3 mm. long, glabrous, the tissue between the slender 

 ribs mostly scarious, the teeth evident, acute, slightly spreading ; flowers several in the involucre ; 

 calyx white, more or less tinged with rose, glabrous without, the outer lobes oblong-obovate ; fila- 

 ments obscurely short-pubescent at base ; ovary scabrous above. 



Sandy or gravelly soils, Upper Sonoran Zone; Coast Ranges, San Luis Obispo and Santa Barbara Counties, 

 California. Type locality: Baron Schroeder's Ranch, 30 miles north of San Luis Obispo, California. May-Sept. 



48. Eriogonum molestum S. Wats. Pine Eriogonum. Fig. 1396. 



Eriogonum molestum S. Wats. Proc. Amer. Acad. 17: 379. 1882. 

 Eriogonum vimineum subsp. molestum Stokes, Gen. Eriog. 50. 1936. 



Annual, the stem usually solitary, branches comparatively few, ascending, 3-8 dm. high, gla- 

 brous and pale glaucous green. Leaves all basal, reniiorm or rounded, 1-2 cm. broad, densely 

 white-tomentose, usually somewhat less so above, crisped or undulate on the margins, petioles 

 exceeding the blades ; bracts glabrous, rather distant ; involucres closely appressed to the stem, 

 4-5 mm. long, glabrous, scarious between the ribs ; flowers several ; calyx white or tinged with 

 rose, 1 . 5 mm. long, glabrous ; outer lobes oblong-obovate, the inner narrower ; achene scarcely 

 exserted, scabrous above. 



Open pine forests, Arid Transition Zone; mountains of southern California, San Bernardino, San Jacinto, 

 and Cuyamaca Ranges. Type locality: mountains of southern California. June- Aug. 



Eriogonum molestum var. Davidsonii (Greene) Jepson, Fl. Calif. 412. 1914. (Eriogonum Davidsonii 

 Greene, Pittonia 2: 295. 1892.) Similar to the typical species in habit but more slender and floral parts 

 smaller; involucre 3 mm. long. Mountains of southern California, mainly in the San Gabriel Mountains. 



49. Eriogonum vimineum Dougl. Wicker Eriogonum. Fig. 1397. 



Eriogonum vimineum Dougl. ex Benth. Trans. Linn. Soc. 17: 416. 1837. 



Annual, with one to several stems from the base, usually becoming well-branched forming a 

 flat-topped or rounded crown, 1-6 dm. high, the lower internodes more or less loosely floccose, 

 upper branches glabrous and green or reddish brown. Leaves all basal or very rarely one or two 

 at the first node, orbicular-obovate, 15-20 mm. long, abruptly contracted to gradually narrowed to 

 the petioles, glabrate above ; ultimate branchlets elongated, slender ; bracts triangular-lanceolate, 

 usually about 1 mm. long ; involucres narrowly cylindric, 2 mm. long, the teeth short, obtuse or 

 rounded; flowers several ; calyx rose-colored or yellowish, 2 mm. long, glabrous or rarely sparsely 

 and inconspicuously glandular toward the base ; outer lobes nearly obovate, the inner a little nar- 

 rower ; filaments glabrous ; achene flask-shaped, the beak longer than the body and scabrous. 



Dry hillsides and plains, especially in sandy soil, Upper Sonoran and Transition Zones; eastern Washington 

 and Rogue River, Oregon, western Nevada, and California to the North Coast Ranges, and central Sierra Ne- 

 vada. Type locality: along the Columbia River, eastern Washington. June— Sept. 



Eriogonum vimineum var. caninum Greene, Fl. Fran. 150. 1891. Stems coriaceous, glabrous or some- 

 what woolly toward the base, reddish, the ultimate branchlets slender; flowers bright, glabrous. This variety 

 replaces the typical form in central California extending from the coast to the Great Valley. Type locality: 

 on dry hills, Tiburon, California. 



Eriogonum pedunculatum Stokes, Leaflets West. Bot. 2: 48. 1937. Slender annual of the general aspect 

 of E. vimineum: involucres pedunculate, the peduncles very slender, erect, almost appressed against the 

 branches of the inflorescence, 1-10 mm. long. Known only from the original collection made on Mokelumne 

 Hill, Calaveras County, California. 



50. Eriogonum mohavense S. Wats. Mojave Eriogonum. Fig. 1398. 



Eriogonum mohavense S. Wats. Proc. Amer. Acad. 12: 266. 1877. 

 Eriogonum delicatulum S. Wats. Proc. Amer. Acad. 17: 379. 1882. 



Annual, the stems solitary to several from the base, glabrous and glaucous, repeatedly tri- 

 chotomously or dichotomously branched, 1-3 dm. high, forming a wide open crown, the ultimate 

 branchlets subcapillary. Leaves all basal, white-floccose, rounded to oblong-obovate, 1-2 cm. 

 long on slender petioles about twice as long ; bracts triangular ; involucres sessile in the forks, and 

 often terminal on the ultimate branchlets, barely 2 mm. long, glabrous except in the throat; 

 flowers usually several ; calyx yellow, about 1 mm. long, glabrous, outer lobes mostly elliptic, the 

 inner a little smaller and narrower ; achene glabrous, 1 . 5 mm. long, more or less exserted. 



Dry desert slopes and washes, Lower Sonoran Zone; western Mojave Desert and Owens Valley, California. 

 Type locality: "Mohave Valley," Mojave Desert, California. June-Aug. 



Eriogonum ampullaceum J. T. Howell, Leaflets West. Bot. 1: 179. 1935. (£. mohavense subsp. ampul- 

 laceum Stokes, Gen. Eriog. 33. 1936.) Annual, the stems erect, 1—2 dm. high, glabrous, di- or trichotonously 

 branched, the branches ascending. Leaves basal, orbicular, 5-10 mm. broad, white-tomentose beneath, floccose 

 above; petioles 5-15 mm. long; bracts triangular, about 1 mm. long; involucres solitary and sessile or subsessile 

 in the axils of the bracts, borne in the upper forks and at the end of the branchlets, turbinate-campanulate, 

 1.5-2 mm. long, microscopically granular, 5-lobed, the lobes rounded; flowers several; calyx ochroleucous, 

 1.25 mm. long, the lobes suborbicular, shorter than the tube, entire; achene flask-shaped, 1 mm. long, the beak 

 muriculate-papillose. Dry desert slopes, Upper Sonoran Zone; Long Valley, Mono County, California. 



Eriogonum Hoffmannii Stokes, Leaflets West. Bot. 1 : 23. 1932. Annual, the stems erect, rather stout, 

 2-4 dm. high, glabrous, di- and trichotomously branched above, occasionally with a few short branches from the 

 base. Leaves basal, suborbicular, subcordate, 2-3 cm. broad, glabrate above, white-tomentose beneath; floral 

 bracts minute, closely subtending the sessile involucres, these borne at the forks and the ends of short pedicel- 

 like branchlets, turbinate-campanulate, 1.5 mm. long; flowers few in each involucre; calyx rose-colored, gla- 

 brous, lobed to near the base, the lobes ovate-lanceolate, not cordate at base; achene slightly exserted. Known 

 only from the vicinity of the type locality, Wild Rose Canyon, Panamint Mountains, Inyo County, California. 



