POLTGONACEiE. (BUCKWHEAT FAMII.Y.) 389 



rough on the margins and veins ; spikes erect, oblong, obtuse, close-flowered ; 

 flowers rose-color ; stamens mostly 8, exserted ; style 2-cleft ; achenium orbic- 

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

 Sept. (J) — Stem 1°- 3° high, sometimes nearly smooth. Leaves 2' -4' long. 

 Spikes I'-l^' long. Elowers much larger than those of the two preceding 

 species. 



* * S/teaths fringed with bristly hairs : achenium S-anffled, or {in No. 5) sometimes 

 lenticular : stamens mostly 8. 



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-cloft ; achenium lenticular or 3-angled, smooth and shining. — Low 

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

 July. (3) — Stem l°-l|^°high. Leaves 2' -4' long, often with a dark trian- 

 gular spot in the middle. Spikes ^'- 1' long. 



6. P. acre, ICunth. 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-angIed. 

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

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

 2' -3' long. 



7. P. hydropiperoldes, 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 rosc-eolor, 

 and, like the leaves, glandless ; stamens 8 ; style 3-eleft ; achenium 3-angled. 

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

 Sept. H. — Stein 2° - 3° long. Leaves 2' - 4' long, not acrid- Spikeg l'-2' 

 long. 



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

 the upper portion, like the peduncles .and lanceolate gjandless leaves, rough with 

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

 spikes filiform, by pairs, loose-flowered ; flowei-s white, glandless ; stamens 8 ; 

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

 Sept. U — 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, glandless ; stamens 8 ; achenium 3-angled. — Pine-barren 

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

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



33* 



