POLYGOXACEAE (BUCKWHEAT FAMILY) 



357 



701. E. pulcher. 

 A bit of inflores- 

 cence x 1. 

 Fruiting calyx x 2. 



702. R. per- 



sicarioides. 



Fruiting 



calyx x 2. 



13. R. PILCHER 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, 2-0 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 

 2-3 long awn-like bristles on each side, and a large 

 grain on the back. (7?. maritimus Man. ed. 6, not 



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

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



2. ACET.6SA [Tourn.] DC. (SORREL.) Flowers dioecious, 

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

 leaves arrow- or halberd- shaped ; smooth perennials, 

 spreading by running rootstocks, flowering in spring. 



15. R. ACETOSA L. (GARDENS.) 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 

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

 lanceolate or linear, halberd-form, at least 



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. 

 - - fa_Q*^Jh 7/2 *y,.v 



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 TroXtf-, many, and y6w, 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-parted, usually more or less herbaceous ; stamens 3-8, the 3 inner 



703. II. Acetosa. 

 Leaf x i/ 2 . 

 Fruiting calyx x 2. 



704. R. hastatulus. 

 Leaf x 



705. R. Acetosella. 

 Leaf x 1. 

 Fruiting calyx x 2. 





