POLYGONACE.E. (BUCKWHEAT FAMILY.) 317 



usually 1 or 2 inches high : leaves linear-oblanceolate, hirsute : bracts un- 

 equal : involucres iu the forks on slender pedicels, the rest more nearly ses- 

 sile : flowers light rose-color. — From Wyoming to Hevada. 



3. OXYKIA, Hill. Mountain Sorrel. 



Flowers perfect. The two inner sepals erect, appressed, and unchanged in 

 fruit. Stamens 6. — Perennial alpine and arctic herbs, erect, with long- 

 petioled round-reniform mostly radical leaves, and small obliquely truncate 

 sheaths : flowers small and greenish, in narrowly panicled racemes. 



1. O. digyna, Campdera. Rather stout and fleshy, 3 to 18 inches high, 

 glabrous : flowers in scarious-bracted fascicles, on short capillary pedicels : 

 sepals often reddish, the outer narrower and carinate. — At high altitudes in 

 cold wet places among rocks throughout the northern hemisphere. 



4. BUM EX, L. Dock. Sorrel. 



Flowers perfect, polygamous, or dioecious. Inner sepals somewhat colored 

 and becoming reticulated {values) in fruit. Stamens G. — Coarse perennial 

 herbs : stems leafy, with obliquely truncate cylindrical naked sheaths : flowers 

 small, fascicled or verticillate in paniculate racemes. 



§ 1. Flowers perfect or polygamous : valves enlarged, often bearing u grain-like 

 callosity on the back : leaves never hastate, pinnately many-veined, rarely very 

 acid. — Docks. 



* Valves wholly without grains, mostly very large (3 lines long or more), entire or 

 denticulate : pedicels long, jointed near the base : glabrous. 



1. R. venosus, Pursh. Stems erect, a foot higll or less, from running 

 rootstocks, stout and leafy, with conspicuous dilated stipules : leaves on short 

 but rather slender petioles, ovate or oblong to lanceolate, 3 to 6 inches long, 

 onhi the lowest acute or somewhat cordate at base: panicle nearly sessile, short, 

 dense in fruit: valves entire, cordate-orbicular with a deep sinus, 9 to 12 lines in 

 diameter, bright rose-color. — From Colorado and Nevada to British Columbia 

 and the Saskatchewan. 



2. R. OCCidentaliS, Watson. Tall and rather slender, often 3 to 6 feet 

 high : leaves oblong-lanceolate, the lowest sometimes ovate, usually narrowing 

 gradually upward from the truncate somewhat cordate base, not decurrent on the 

 slender often elongated petiole, often a foot long or more: panicle narrow, elon- 

 gated, nearly leafless: valves broadly cordate, with a very shallow sinus, 3 lines 

 in diameter] often denticulate near the base.— Proc. Amer. Acad. xii. 253. 

 Ji. longifolius of authors, not of DC. From New Mexico and Colorado to 

 Labrador and Alaska. 



* * Valves smaller, one or more of them grain-bearing. 

 3 B. salicifolius, Weinman. Slender, often low, 1 to 5 feet high, usu- 

 ally branching and decumbent at base, glabrous : leaves narrowly or linear- 

 lanceolate, or the lowest oblong, 3 to 6 inches long, attenuate into a short peti- 

 ole not undulate, glaucous : panicle usually open, the flowers crowded upon the 

 branches : valves ovate-rhomboidal to broadly deltoid, entire or denticulate, usually 

 with very large callosities.— Across the continent and northward to Alaska. 



