POLYGONACE^E. (BUCKWHEAT FAMILY.) 415 



edons slender. — Pedicels jointed. Ours all herbaceous, flowering through late 

 summer and early autumn. (Name composed of noXv, many, and youv 7 knee, 

 from the numerous joints.) 

 § 1. BISTORTA, Tourn. Calyx petal-like, deeply 5-clefl: stamens 8 or 9 : styles 



3, slender: achenium 3-sided: stems low and simple from a thick and woody 



creeping rootstock: Jlowers in a spike-like raceme. 



1. P. viviparum, L. (Alpine Bistort.) Smooth, dwarf (4' -8' high), 

 bearing a linear spike of flesh-colored flowers (or often little red bulblets in their 

 place) ; leaves lanceolate. — Alpine summits of the White Mountains, New Hamp- 

 shire, shore of Lake Superior, and northward. (Eu.) 



§2. PERSIC ARIA, Tourn. Calyx petal-like, 5-parted : stigmas capitate : ache- 

 nium lenticular, or (when there are 3 stigmas) 3-sided: cotyledons accumbent and 

 albumen hurd and horny except in No. 2 : roots Jibrous : Jlowers crowded in 

 spikes or spike-like racemes. 



« Sheaths some of them with an abrupt spreading and more or less foliaceous (some- 

 times deciduous) border: tall branching annuals, with panicled and nodding dense 

 cylindrical spikes : flowers rose or flesh-color : achenium flat. 



2. P. orientals, L. (Prince's Feather.) Soft-hairy; leaves ovate or 

 oblong, pointed, distinctly petioled; flowers large, bright rose-color; stamens 7 ; 

 style 2-cleft; cotyledons incumbent; albumen floury. — Sparingly escaped 

 from gardens into waste grounds. (Adv. from India.) 



3. P. Careyi, Olney. Stem (3° -5° high) and peduncles glandular-bristly; 

 leaves lanceolate, roughish ; flowers purplish ; stamens mostly^ 5 ; style 2-parted. — 

 Shady swamps, Rhode Island to New Jersey, Pennsylvania, and northward. 



* * Sheaths all cylindrical and truncate, without, a border. 

 *- Annuals: spikes oblong or linear, densely flowered : flowers rose or flesh-color , or 

 occasionally varying to white, slightly or not at all glandular-dotted : stamens 6 - 8 : 

 styles 2 or 2-clefl and achenium flattened, except sometimes in No. 7, which alone, 

 has the sheaths at all or more than slightly cdiate. 



4. P. Pennsylvanicum, L. Stem (L°-3°high), smooth below, the 

 branches above, and especially die peduncles, beset with bristly-stalked glands ; leaves 

 lanceolate, roughish on the midrib and margins (l^'-5' long) ; spikes oblong, 

 obtuse (I' -2' long), erect, thick; stamens mostly 8, somewhat exserted ; style 2-cleft; 

 achenium with flat sides. — Moist soil, in open waste places : common. 



5. P. incarnatum, Ell. Nearly glabrous (3° -6° high) ; the peduncles,, 

 &c. often minutely rough with scattered sessile glands ; sheaths wholly nakec 

 and glabrous ; leaves rough on the midrib and margins, elongated-lanceolate 

 (4' -12' long, l'-3' wide below), tapering gradually from towards the base to a 

 narrow point; spikes linear, nodding, becoming slender (l£'-3' long) ; stamens 

 6 and styles 2, both included; achenium with concave sides. (P. nodosum, var. 

 incarnatum, Ed. 2. P. lapathifolium, Amer. authors, $*c.) — Wet borders of 

 ponds and streams ; rather common everywhere, especially southward and 

 westward. — Flowers smaller than in the last, lighter rose-color, or flesh-color, 

 varying to white. 



6. P. lapathifblium, Ait., is lower, with shorter and much less pointed 

 leaves ; sheaths often somewhat hairy or ciliolate ; spikes oblong and blunt ; flowers 



