438 POLYGONACE^. (UUCKWHEAT FAMILY.) 



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

 ++ Indigenous ; leaves not wavij, none heart-shaped , except the lowest ofn. 5. 



2. R. Brit^nnica, L. (Great Water-Dock.) Tall and stout (5 - G** 

 high) ; leaves oljloug-lauceolate, rather acute at both euds, transversely veined, 

 and with obscurely erose-crenulate margins (the lowest, including the petiole, 

 1-2^ long, the middle rarely truncate or obscurely cordate at base) ; racemes 

 upright in a large compound pauicle, nearly leafless ; Avhorls crowded ; pedicels 

 capillar ji, nod ding, about twice the length of the fruiting calyx ; the valves orbiculai 

 or round-ovate, very obtuse, obscurely heart-shaped at base, Jinely reticulated. 

 entire or repand-denticulate (2 - 3" broad), all grain-bearing. (R. orbiculatus, 

 Grai/.) — Wet places, X. Eng. to N. J., west to Minn, and Kan. 



3. R. altissimus, Wood. (Pale Dock.) Rather tall (2-6° high); 

 leaves ovate- or ohlong-lanceolate, acute, pale, thickish, obscurely veiny (the cau- 

 line 3-6' long, contracted at base into a short petiole) ; racemes spike-like 

 and panicled, nearly leafless ; whorls crowded; pedicels nodding, shorter than 

 the fruiting calyx; valves broadly ovate or obscurely heart-shaped, obtuse or 

 acutish, entire, loosely reticulated (about 2" broad), one with a conspicuous 

 grain, the others with a thickened midrib or naked. (R. Britannica, Gray; 

 not L) — Moist grounds, N. Y. and X. J. to Minn, and Kan. 



4. R. salicifolius, Weinmann. (White Dock.) Rather low (1-3° 

 high); root white; leaves narrowly or linear-lanceolate, or the lowest oblong; 

 whorls much crowded; pedicels much shorter than the fruiting calyx; valves 

 deltoid-ovate, obtusish or acutish (about 1^" long), one, two or sometimes all 

 with a conspicuous often very large grain ; otherwise nearl}^ as n. 3. — Salt 

 marshes, from Xewf. to X. Eng., about the Great Lakes, and far westward. 



5 R. verticillatUS, L. (Sw^amp Dock.) Rather tall (3-5° high); 

 leaves lanceolate or oblong-lanceolate, rather obtuse, thickish, pale-green, the 

 lowest often heart-shaped at base ; racemes nearly leafless, elongated, loose, the 

 whorls crowded or the lower ones distant ; fruit-bearing pedicels slender, club- 

 shaped, abruptly rejiexed, 3-4 tiines longer than the fruiting calyx ; valves dilated- 

 rhomboid, obtusely someichat pointed, strongly rugose-reticulated, each bearing a 

 very large grain. — Wet swamps, common. 

 •"1- -^ Naturalized European weeds ; lower leaves mostly heart-shaped at base. 



R. CRfspus, L (Curled Dock.) Smooth (3-4° high); leaves ivith 

 strongly ivavy-curled margins, lanceolate, acute, the lower truncate or scarcely 

 heart-shaped at base; ivhorls crowded in prolonged ivand-like racemes, leafless 

 above ; valves round-heart-shaped , obscurely denticulate or entire, mostly all grain- 

 bearing. — In cultivated and waste ground, very common. A hybrid of this 

 with the next is reported from ]VIass., X. Y., and Md. 



R. obtusif6lius, L. (Bitter Dock.) Stem roughish ; loivest leaves 

 ovate-heart-shaped , obtuse, rather downy on the veins beneath, somewhat wavy- 

 margined, the upper oblong-lanceolate, acute; ivhorls loose and distant : valves 

 ovate-halberd-s/iaped, ivith some sharp awl-shaped teeth at base, strongly reticu- 

 lated, one of them principally grain-bearing. — Fields, etc., common. 



R. SANOL'fxEUS, L. Leaves oblong-lanceolate, often fiddle-shaped, wavy- 

 margined; ivhorls distant, in long slender leafless spikes; pedicels very short, 

 jointed at base ; valves nan-owl y oblong, obtuse, entire, one at least grain-bearing ; 

 veins of the leaf red, or green. — Waste and cultivated ground. 



R. coxGLo:\iERA.Trs, Murray, (Smaller Green Dock.) Like the last, 

 but leaves not fiddle-shaped, and panicle leafy; pedicels short, jointed below 

 the middle ; valves acutish, all grain-bearing. — Moist places. 



