POLYGON ACEAE (BUCKWHEAT FAMILY) 



357 



13. R. PULCHER L. Leaves oblong, frequently constricted 

 above the base, mostly acute ; valves ovate, many-toothed, 

 soon coriaceous, very strongly reticulated. — Ballast grounds, 

 etc., Va. to La. ; Cal. (Adv. from Eu.) Fig. 70L 



14. R. persicarioides L. (Golden D.) Mi- 

 nutely pubescent, diftusely branched, 2-0 dm. high ; 

 leaves lance-linear, wavy-margined, the lower au- 

 ricled or heart-shaped at base ; whorls excessively 



701 E Dulcher crowded in leafy and compact or interrupted spikes ; 



A bit of inflores- "^^^^^^ rhoiubic-oblong, lance-pointed, each bearing 



ceiice X 1. 2-3 long awn-like bristles on each side, and a large 



Fruiting calyx x 2. grain on the back. (B. maritimus Man. ed. 6, not 



L.) — Sea-shore, Que. to N. C. ; also in brackish or saline places, 

 Out. to 111., and westw. Fig. 70S. 



\v 



70-2. R. per- 

 sicariuides. 



Fruiting 

 calvx X 2. 



703. \l. Acetosa. 

 Leaf X 1/2- 



§ 2. ACETOSA [Tourn.] DC. (Sorrel.) Flowers dioecious, 

 small, in a terminal naked panicle ; herbage sour; some 

 leaves ai^oio- or halberd-shaped; smooth perennials, 

 spreading by running rootstocks, flowering in spring. 



15. R. Acet6sa L. (Garden S.) Erect, 

 3-9 dm. high ; leaves oblong or broadly 

 lanceolate, arrow-shaped ; valves rounded at 

 the apex, 4 mm. broad. — Lab. to Pa., and 

 westw. ; frequent near Quebec, compara- 

 tively local southw. (Nat. from Eu.) Fig. 

 703. 



16. R. hastatulus Baldw. Stem simple, 

 3-6 dm. high ; leaves linear or lanceolate, 

 some of them hastate with divaricate basal 

 lobes ; valves ovate, 2.5 mm. broad. — Sandy 

 soil, near the coast, e. Mass. to Fla. and 

 Tex. ; inland in Miss, basin to 111., Mo., and 

 Kan. Fig. 704. 



17. R. Acetosella L. (Field or Sheep 



Fruitin- calvx X '> ^'^ ^^^ ^^~^ ^™- ^^S^) 5 \e^^^^ narrow- 704. E. hastatulus. 

 " • "■ lanceolate or linear, halberd-form, at least Leaf x 1/2- 



the lowermost, the narrow lobes entire, widely spreading ; Fruiting calyces x 2. 



pedicels jointed at the summit; sepals 

 scarcely enlarged in fruit, exceeded, by the naked achene. 

 — A common weed. (Nat. from Eu.) Fig. 705. 



4. POLYGONUM [Tourn.] L. Knotweed 



Calyx 4-6 (mostly 5) -parted; the divisions often petal- 

 like, all erect in fruit, withering or persistent. Stamens 

 3-9. Styles or stigmas 2 or 3 ; achene accordingly lentic- 

 ular or 3-angular. Embryo placed in a groove on the 

 outside of the albumen and curved halfway around it ; the radicle and usually 

 the cotyledons slender. Pedicels jointed. — Ours all herbaceous, w'th fibrous 

 roots (except in P. viviparum), flowering through late summer and early 

 autumn. (Name composed of iroXv-, many, and yow, knee, from the numerous 

 joints.) 



§ 1. AVICULApIA Meisn. Flowers in axillary fascicles or spicate icith folia- 

 ceous bracts ; leaves and bracts jointed xipon a very short petiole adnate to 

 the short sheath of the 2-lobed or lacerate scarioiis stipules; stems striate ; 

 calyx 5-G-parted, usually more or less herbaceous ; stamois 3-8, the 3 iniier 



705. E. Acetosella. 

 Leaf X 1. 

 Fruiting calyx x 2. 



