438 POLYGONACE^E. (BUCKWHEAT FAMILY.) 



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

 ^Indigenous; leaves not wavy, none heart-shaped, except the lowest ofn. 5. 



2. R. Britannica, L. (GREAT WATER-DOCK.) Tall and stout (5 - 6 

 high) ; leaves oblong-lanceolate, rather acute at both-ends, 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 panicle, nearly leafless ; whorls crowded ; pedicels 

 capillary, nod ding, about twice the length of the fruiting calyx ; the valves orbicular 

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

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

 Gray.) Wet places, N. Eng. to N. J., west to Minn, and Kan. 



3. R. altissimus, Wood. (PALE DOCK.) Rather tall (2-6 high); 

 leaves ovate- or oblong-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 N. J. to Minn, and Kan. 



4. R. salicifdlius, 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 l" long), one, two or sometimes all 

 with a conspicuous often very large grain ; otherwise nearly as n. 3. Salt 

 marshes, from Newf. to N. Eng., about the Great Lakes, and far westward. 



5 R. verticillatus, L. (SWAMP 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 reflexed, 3-4 times longer than the fruiting calyx ; valves dilated- 

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

 very large grain. Wet swamps, common. 

 t-f *- Naturalized European weeds ; lower leaves mostly heart-shaped at base. 



R. CRlspus, L. (CURLED DOCK.) Smooth (3-4 high); leaves with 

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

 heart-shaped at base ; whorls crowded in prolonged wand-like racemes, leafless 

 above ; voices 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 Mass., N. Y., and Md. * 



R. OBTUSIF6LIUS, L. (BITTER DOCK.) Stem roughish; lowest leaves 

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

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

 ovate-halberd-shaped, with some sharp awl-shaped teeth at base, strongly reticu- 

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



R. SANGirfNEUS, L. Leaves oblong-lanceolate, often fiddle-shaped, wavy- 

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

 jointed at base ; valves narrowly oblong, obtuse, entire, one at least grain-bearing ; 

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



R. CONGLOMERATUS, 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, 



