490 ORDER CII. POLYGONACE.E. 



d. Flowers in racemose panicles. Leaves subcordate or sagittate. 



13. P. sagitta'tum, (Mich.) Stem slender, climbing, angled, retrorsely 

 serrate. Leaves nearly sessile, glabrous, sagittate. Flowers axillary 

 and terminal, in small compact heads, on long peduncles. Stamens 8. 

 Styles 3-cleft. Perianth white. — 0. July — Aug. Wet grounds. 



14. P. arifo'lium, (Mich.) Stem retrorsely aculeate, prostrate, flex- 

 uous, sometimes climbing, squ ire, pubescent. Leaves hastate, on long 

 petioles, pubescent. Spikes few-flowered, terminal and axillary. Sta- 

 mens 6. Styles bifid. — %. Aug. — Sept. Wet grounds. 



15. P. convol'vulus, (Mich.) Stem long, climbing, angular, some- 

 what rough. Leaves petioled, hastate-cordate, with spreading lobes. 

 F'owers in axillary racemes. Stamens 8. Style 3-cleft. Perianth 

 whitish or reddish. — $j>. July — Aug. In fields. 



16. P. scan'dens, (Mich.) Stem climbing, glabrous, bright purple, an- 

 gled. Leaves broad-cordate, with the margins and veins slightly sca- 

 brous. Flowers in axillary racemes, large. Stamens 8. Styles 3. Pe- 

 rianth winged, white, or reddish. — 0-. July — Aug. Shady woods. 



P. dumttosum. 



17. P. fagopy'rum, (L.) (Y vom fagus, beech, and puros, wheat, from 

 the resemblance of the nut to the beechnut. The English name is from 

 the German buche, beech, compounded with wheat, making Buckwheat, 

 nr Beechwheat.) An annual plant, with triangular-cordate leaves. 

 Flowers in paniculate racemes, or corymbose, white or greeni.-h. 



Fagopyrum esctdentum, Mcench. 



Genus III— RU'MEX. L. 6—3. 

 (From rumo, to suck ; the Romans sucked the leaves to allay thirst) 



Perianth 6-leaved, in 2 rows. Stamens 6. Styles 3. Nut 

 triquetrous, inclosed by the three interior valves of the perianth. 

 Stigmas many-cleft. 



1. R. sanguineus, (L.) Stem erect. Radical leaves large, entire, cor- 

 date-lanceolate, variegated with red veins. Flowers in small, distant 

 whorls. Perianth persistent, marked on the back with red grains. — 

 71. June — July. Infields. 3 feet. BUody Dock. 



2. R. pui/cher, (L.) Radical leaves oblong, with a sinus on each 

 side; cauline leaves entire. Perianth toothed. — %. June — July. In- 

 troduced. 



3. R. verticilla'tus, (L.) Leaves long, lanceolate, narrow, acute, 

 with cylindrical sheaths. Flowers whorled, in simple racemes. Leaves 

 of the perianth entire, each bearing a vein on the back. Pedicels thick, 

 half an inch long. — If. June — July. Wet grounds. 1 — 2 feet. 



Swamp Pock. 



4. R. Britan'nicus, (L.) Stem branching, tinged with red, furrowed. 

 Ljcaves broad-lanceolate, flat, alternate. Flowers in leafless whorls, form- 

 ing a compound terminal panicle, polygamous. — 2f. April — May. 

 Swamps. 2 — 3 feet. 



6. R. cris'pus, (L.) Stem erect, angled. Radical leaves lanceolate, 





