POLYGON ACEAE (BUCKWHEAT FAMILY) 



357 



701. R. pulcher. 



702. R. per- 



bicarioldes. 



Fruiting 



calyx xl. 



13. R. PILCHES 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. 701. 



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

 nutely pubescent, diffusely branched, 2-tf dm. high ; 

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

 ricled or heart-shaped at base ; whorls excessively 

 crowded in leafy and compact or interrupted spikes ; 

 valves rhombic-oblong, lance-pointed, each bearing 



A bit of inflores- _ . ' , 



cence x i. 2-3 long awn-like bristles on each side, and a large 



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



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

 Ont. to 111., and westw. FIG. 702. 



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

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

 leaves arrow- or halberd-shaped; smooth perennials, 

 spreading by running rootstocks, flowering in spring. 



15. R. AcEx6sA L. (GARDENS.) Erect, 

 3-9 dm. high ; leaves oblong or broadly 

 lanceolate, arroio-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 

 S.) Low (1-3 dm. high) ; leaves narrow- 



x 2> lanceolate or linear, halberd-form, at least Lea f x %. 

 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. 706. 



703. It. Acetosa. 

 Leaf x %. 



704. B . hasutulus. 



706. E. Acetosella. 

 Leaf x 1. 

 Fruiting calyx x 2. 



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, with fibrous 

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

 autumn. (Name composed of n-oXiJ-, many, and 76, knee, from the numerous 

 joints.) 



1. AVICULARIA Meisn. Flowers in axillary fascicles or spicate with folia- 

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

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

 calyx 5-6-pared, usually more or less herbaceous ; stamens 3-8, the 3 inner 



