POLYGONACEJS. (BUCKWHEAT FAMILY.) 380 



rou^h on the margins and veins ; spikes erect, oblong, obtuse, close-flowered ; 

 Bowers rose-color ; stamens mostly 8, exserted ; style 2-eleft ; achenium orbic- 

 ular, with the sides concave. — Wet places, Georgia, and northward. July- 

 Sept. (T) — Stem 1°- 3° high, sometimes nearly smooth. Leaves 2' -4' long. 

 Spikes l'-\k' long. Flowers much larger than those of the two preceding 

 6pecics. 



* * iSheaths friiujed with bristly hairs : achenium 3-angled, or (in Xo. 5) sometimes 

 lenticular: stamens mostly S. 



5. P. Persicaria, L. Stem smooth, branching from the base, erect or 

 diffuse ; leaves lanceolate or oblong, obtuse or acutish, the margins and veins 

 roughened ; sheaths short, nearly smooth, fringed with a few short bristles ; 

 spikes short, oblong, obtuse, dense-flowered ; flowers rose-color ; stamens 6 - 7 ; 

 style half 2-cleft ; achenium lenticular or 3-nngled, smooth and shining. — Low 

 places around dwellings and along roads, Florida, and northward. Introduced. 

 July. © — Stem 1°-U°high. Leaves 2' -4' long, often with a dark trian- 

 gular spot in the middle. Spikes ¥ -I' long. 



6. P. acre, Kunth. Stem slender, smooth, creeping at the base ; leaves 

 lanceolate, rough on the margins and veins, and, like the white calyx, dotted 

 with pellucid glands ; sheaths smoothish, long-fringed at the throat ; spikes 

 1-3, filiform, loose-flowered; stamens 8; style 3-parted ; achenium 3-angled. 

 (P. punctatum, Ell.) — Ditches and margins of ponds, Florida, and northward. 

 July - Sept. 1J. — Stem 1° - 3° long. Leaves 2' - 4' long, very acrid. Spikes 

 2' - 3' long. 



7. P. hydropiperoid.es, Michx. Stem slender, smooth, ascending from 

 a floating or creeping base ; leaves linear or lanceolate, roughened with short 

 rigid hairs on both sides, or only on the margins and veins ; sheaths hispid, 

 long-fringed ; spikes 2-3, linear, rather close-flowered ; calyx pale rose-color, 

 and, like the leaves, glandlcss ; stamens 8 ; style 3-clefc ; achenium 3-angled. 

 (P. mite, Pars.) — Ditches and muddy banks, Florida, and northward. July - 

 Sept. y. — Stem 2° -3° long. Leaves 2' -4' long, not acrid. Spikes 1'- 2' 

 long. 



8. P. setaceum, Baldw. Stem erect, sparingly branched, smooth below, 

 the upper portion, like the peduncles and lanceolate glandlcss leaves, rough with 

 appressed hairs ; stipules appressed-hirsute, copiously fringed with long bristles ; 

 spikes filiform, by pairs, loose-flowered; flowers white, glandlcss; stamens 8; 

 style 3-cleft ; achenium 3-angled. — Low ground, Georgia and Florida. July- 

 Sept. I]. — Stem 2° - 3° high. Leaves 3'- 5' long. Spikes 1'- 2' long. 



9. P. hirsutum, Walt Stem erect, densely hirsute with spreading ful- 

 vous hairs ; leaves lanceolate, nearly sessile, rounded at the base, hirsute, partic- 

 ularly on the veins and margins; sheaths hirsute, copiously fringed; spikes 

 2 - 3, linear, erect, rather close-flowered ; peduncles smooth above ; bracts 

 naked ; flowers white, glandlcss ; stamens 8 ; achenium 3-angled. — Pine-barren 

 ponds, Florida to North Carolina. July -Sept. 1J. — Stem 2° - 3° high. 

 Leaves 2' -3' long. Spikes 1' long. 



