388 POLYGONACEJE. (BUCKWHEAT FAMILY.) 
7. P. articulata, Meisner. Annual; stem much branched, slender ; leaves 
narrowly linear, obtuse, deciduous; sheaths truncate, pointless ; racemes numer- 
ous, erect, slender ; bracts truncate, open, the lowest ones pointed ; flowers bright 
rose-color ; sepals oval or roundish, nearly equal, unchanged in fruit; interior 
filaments rhombic-ovate at the base. (Polygonum articulatum, L.) — Dry sandy 
soil, Georgia, and northward. Aug.— Stem 6'- 12 high. Leaves 4!~8 long. 
Racemes 1' - 3! long. : 
3. POLYGONUM, L. Kworwrrp. 
Flowers perfect. Calyx 5- (rarely 4-) parted, corolla-like, the lobes nearly 
equal, erect and unchanged in fruit. Stamens 3—9: anthers roundish. Styles 
2-3, distinct or partly united: stigmas entire. -Achenium 3-angled or lenticu- 
lar, enclosed in the persistent calyx. Embryo curved on the outside of the 
albumen. Radicle slender. — Herbs, with alternate, simple leaves, and sheath- 
ing stipules. Flowers commonly white or rose-color, variously disposed. 
$ 1. AwnLYcOoNON. Flowers in closely-bracted spikes: stamens 7: style 2-cleft: 
achenium lenticular : cotyledons incumbent : albumen mealy. 
1. P. orientale, L. Hairy; stem tall, branching; leaves ovate, acumi- 
nate, petioled ; sheaths loose, salver-form ;spikes panicled, cylindrical, dense, 
nodding ; bracts ovate; flowers large, bright rose-color.— Around dwellings, 
escaped from cultivatioa. June-Sept.—Stem 3°-5° high. Spikes 2'-3' 
$ 2. Persicaria. Flowers in closely-bracted spikes: stamens 4-8: styles 2-3, 
or 2—3-cleft: achenium 3-angled or lenticular: cotyledons accumbent : albumen 
horny : sheaths cylindrical, truncate. 
* Sheaths naked : style 2-cleft or 2-parted: achenium lenticular. 
2. P. incarnatum, Ell Stem smooth below, the summit of the branches, 
peduncles, and calyx sprinkled with glandular dots; leaves lanceolate, long: 
acuminate, petioled, rough on the margins and veins; sheaths slender, appressed ; 
spikes racemed, linear, nodding ; bracts spreading, acute, longer than the pe : 
cels ; flowers small, flesh-color. Stamens 6; style 2-parted ; achenium ovate, 
with the sides concave.— Ponds, ditches, &c., South Carolina, and d 
ward. July-Oct. @—Stem 29-39 high. Leaves 6'+8' long. Spikes!'- 
long. . 7 : 
3. P. densiflorum, Meisner. Stem stout, smooth, tumid at the joints, 
_ branelfing above; leaves lanceolate or oblong-lanceolate, tapering at the sa 
mit, but rather obtuse, rough on the margins and veins; spikes T 
Somewhat panicled, linear, erect, dense-flowered, the peduncles minutely gaw, 
