POLYGONACEAE. 83 



long or longer; umbels 6-10-rayed, mostly compound, rather dense; principal 

 bracts linear or oblanceolate; branches very short or 2-4 cm. long; involucres 

 pubescent, deeply 5-lobed, the lobes acute, spreading; flowers white or yellow, 

 sparsely pilose. Rocky places both at low altitudes and in the mountains. 



Eriogonum compositum leianthum Benth. Perianth glabrous, usually yel- 

 low. In rocky places. 



Eriogonum stellatum Benth. In loose tufts, woody at base, somewhat 

 tomentose; stems erect or ascending, 20-30 cm. high; leaves oblanceolate to 

 broadly oval, obtuse, green and glabrate above, densely white tomentose 

 beneath; peduncle simple or branched, naked or with a single bract in the 

 middle; bract of the involucre leaf-like; umbel compound; perianth bright 

 yellow, glabrous. Common on stony hillsides in the Blue Mountains. 



Eriogonum heracleoides Nutt. Loosely tufted, thinly tomentose through- 

 out; flowering stems erect, 20-40 cm. tall, with a single whorl of leaves half 

 way up; leaves linear to oblanceolate, acute, 3-5 cm. long, attenuate at base 

 into a short petiole, paler and more pubescent beneath; bracts similar to the 

 leaves, but smaller; umbels 1-10-rayed, simple or compound; involucres woolly, 

 deeply lobed, the lobes reflexed; flowers whitish. Common on basaltic ledges. 



Eriogonum niveum Dougl. Densely white-tomentose throughout; stem 

 tufted from a loose woody caudex, 30-50 cm. tall, loosely several-times forked, 

 the branches in twos or threes, ascending; basal leaves ovate or oblong, obtuse, 

 1-3 cm. long, densely white-woolly on each side, on slender petioles; cauline 

 narrower, nearly sessile, whorled at the forks, the upper reduced; umbels in 

 the forks or on the sides of the branches; involucre short and broad, 4 mm. long, 

 5-6-toothed, the tips somewhat recurving; flowers white or pinkish, 4-5 mm. 

 long. In stony soil, abundant in the sagebrush region. 



Eriogonum vimineum Dougl. Annual; stems wiry, erect, 15-40 cm. tall, 

 much branched above the base, tomentose below, the branches long and 

 slender; leaves commonly in a single rosette at or near the base, broadly oblong 

 or orbicular, 2-4 cm. long, densely tomentose beneath, less so above; petiole 

 slender, about as long as the blade; umbels small, 2-8-flowered, sessile and 

 scattered along the sides of the long branches, or in the forks; involucres 

 narrow, 3-4 mm. long, 5-toothed and nerved, glabrous; flowers white or pink, 

 2 mm. long. In basaltic gravel or sandy soil in the warmer valleys. 



Eriogonum strictum Benth. Whole plant white-tomentose; stems slender, 

 woody, 20-30 cm. high; leaves elliptical to oblanceolate, acute, 1-2 cm. long, 

 slender-petioled, mostly on short branches from the caudex; flowers yellowish- 

 white in a loose 2-3-times branched panicle; umbels solitary, in a forked cyme, 

 with some scattered along the branches; involucres tomentose within, but 

 merely pilose without. In the higher Blue Mountains, rare. 



114. RUMEX. Dock. 



Perennial or annual leafy-stemmed herbs, some species slightly 

 woody; stem grooved, mostly branched; leaves entire or undu- 

 late, flat or crisped; sheaths usually cylindric, brittle, soon falling 

 away; inflorescence of simple or compound often panicled 

 racemes; flowers green or reddish, perfect, dioecious or polygamo- 

 monoecious, whorled, on jointed pedicels; calyx 6-parted, the 

 three outer sepals unchanged in fruit, the three inner ones mostly 

 developed into valves which are entire, dentate or fringed with 

 bristle-like teeth; stamens 6; stigmas tufted; akene 3-angled, the 

 angles more or less margined. 



