152 POLYGONACEAE (BUCKWHEAT FAMILY) 



floccosely tomentose, leafy below only: leaves from oblong to linear, mostly 

 obtuse at the apex, nearly sessile or short-petioled : inflorescence a corymbose 

 compound cyme, often quite large, effusely branched and carried on a long 

 rigid naked peduncle: calyx white or rose-colored, seldom more than 2 mm. 

 long, at length constricted near the middle: stamens and style-branches in- 

 cluded. (Includes E. microthecum Nutt. 1. c. 172; E. tristichum Small, 1. c. 55; 

 E. salicinum Greene, PI. Baker 3: 16. 1901.) From Nebraska and New 

 Mexico to the Pacific. 



29. Eriogonum corymbosum Benth. in DC. Prodr. 14: 17. 1856. Allied to 

 the foregoing but stouter, less branched, the branches more rigid and often 

 erect, leafy to near the shorter and more compact cyme: leaves oblong or nar- 

 rower, obtuse and inclined to be undulate-crisped on the margins: bracts 

 triangular-subulate: calyx broadly campanulate, at length constricted near 

 the middle; the inner segments emarginate, shorter than the outer: style 

 branches exserted. [E. Fendleriana (Benth.) Small; E. divergens Small, 1. c. 

 55.] From Kansas to Arizona and Oregon. 



30. Eriogonum caespitosum Nutt. Journ. Acad. Phila. 7: 50. 1834. Matted- 

 caespitose: leaves 6-12 mm. long, mostly rosulate on the prostrate branches of 

 the caudex, spatulate, hoary-tomentose on both sides, the margins more or 

 less revolute: scapes leafless, 3-8 cm. high: involucre solitary, naked, deeply 

 6-8-cleft; the lobes narrow, spreading and at length reflexed: calyx 4-6 mm. 

 long, yellow or tinged with purple, slightly silky-villous, abruptly contracted 

 at base; its segments oval, the inner and the filaments more or less villous at 

 base: ovary sparingly hirsute above. Wyoming to Washington. 



31. Eriogonum andinum Nutt. Journ. Acad. Phila. II. 1: 160. 1847. 

 Very similar to the preceding, more depressed-caespitose : leaves smaller and 

 densely pilose-lanate: peduncle short and weak: ovary (achene) glabrous. 

 Western Wyoming to Nevada. 



32. Eriogonum chrysocephalum Gray, Proc. Am. Acad. 11: 101. 1876. 

 Caudex diffusely branched, woody, tomentose throughout: leaves narrowly 

 oblanceolate, 3-5 cm. long, sometimes nearly glabrous above: peduncle simple 

 erect, 5-15 cm. high; the inflorescence capitate or but slightly branched: 

 involucres narrowly turbinate, firm, about 3 mm. long, short-toothed, some- 

 what tomentose: flowers yellow, glabrous. (E. laxifolium A. Nels. Bot. Gaz. 

 34: 23. 1902.) Western Wyoming and Utah. 



33. Eriogonum orendense A. Nels. Bot. Gaz. 34: 21. 1902. Caudex woody, 

 almost wholly subterranean, tufted, tomentum uniform and rather dense 

 throughout: stems numerous, short: leaves crowded, narrowly oblong or 

 oblanceolate, subacute, slender-petioled : scapes 7-15 cm. high; the inflores- 

 cence subumbellate, with short subulate bracts; the rays unequal: involucres 

 few in each cyme, short-peduncled, turbinate, merely toothed around the 

 summit, 3 mm. long, many-flowered: calyx bright-yellow; the segments simi- 

 lar, oblong, obtuse, scarcely 2 mm. long; the pedicels intermingled with setae 

 bearing stipitate glands and a few fine slender hairs: filaments pubescent: 

 styles long-exserted: ovary glabrous. Desert areas; Wyoming to Utah. 



34. Eriogonum campanulatum Nutt. Journ. Acad. Phila. II. 1: 163. 1848. 

 Caespitose shrubby, the woody leafy branches short, bearing a naked elongated 

 herbaceous scape-like peduncle: leaves 3-6 cm. long, from linear to spatulate- 

 oblanceolate, attenuate into a slender petiole, white-woolly on both sides or 

 becoming glabrate above, the margins at length mostly revolutc: scapes rigid, 

 1-2 dm. long, the cyme repeatedly trichotomous, calyculately bracted at the 

 nodes: involucres 5-toothed, soon glabrate: calyx yellow, its lobes oblong or 

 fiddle-shaped: style and style-branches exserted. From Nebraska to New 

 Mexico and west to Oregon. 



2. OXYRIA Hill. MOUNTAIN SORREL 



Perennial alpine and arctic herbs, erect, with long-pctioled round-reniform 

 0IO8tly radical Ic.-ivos, :md small obliquely truncate sheaths. 1 'lowers small and 

 greenish, in narrowly panicled racemes, perfect. The two inner sepals erect, 



