Genus 7. 



BUCKWHEAT FAMILY 



10. Persicaria opelousana (Riddell) 



Small. Opelousas Persicaria. 



Fig. 1639. 



Polygonum opelousanum Riddell ; Small, Bull. Torr. 



Club 19: 354. 1892. 

 Persicaria opelousana Small, Fl. SE. U. S. 378. 1903. 



Perennial, glabrous or nearly so throughout, 

 stem slender, erect or ascending, sparingly or 

 considerably branched, i°-3° tall, becoming woody 

 below. Leaves linear or linear-lanceolate, ii'— 5' 

 long, sessile, ciliate ; ocreae cylindric, strigose, 

 fringed with slender bristles ; spicate racemes 

 panicled, erect, often geminate, ¥-2' long, not 

 densely flowered ; calyx greenish-white, pedicelled, 

 S-parted to below the middle ; stamens 8 or fewer, 

 included ; style deeply 3-parted ; achene 3-angled 

 or rarely 4-angled, broadly ovoid or obovoid, $"- 

 1" long, black, smooth and shining. 



In wet soil, Massachusetts and Missouri to Louis- 

 iana, Texas and Mexico. July-Sept. 



11. Persicaria hydropiperoides (Michx.) 

 Small. Mild Water Pepper. Fig. 1640. 



P. hydropiperoides Michx. Fl. Bor. Am. 1: 239. 1803. 

 Polygonum mite Pers. Syn. 1 : 440. 1805. 

 Persicaria hydropiperoides Small, Fl. SE. U. S. 378. 1903. 

 Polygonum hydropiperoides Macouni Small, Mem. Dept. 

 Bot. Col. Coll. 1 : 81. 1895. 



Perennial, glabrous or strigillose, stem erect, decum- 

 bent or prostrate, simple or branched above, slender, 

 i°-3° long. Leaves narrowly lanceolate or oblong- 

 lanceolate, varying to linear-lanceolate, 2'-6' long, 

 short-petioled, ciliate, pubescent with appressed hairs 

 on the midrib beneath ; ocreae cylindric, loose, strigose, 

 fringed with slender bristles; racemes panicled, ter- 

 minal, erect, narrow, more or less interrupted, 1F-3' 

 long; calyx white, pink or purplish-pink; stamens 8; 

 style 3-parted to below the middle ; achene 3-angled, 

 ovoid or oblong, l"-li" long, smooth, shining. 



In swamps and wet soil, New Brunswick to Minnesota 

 and California, south to Florida and Mexico. June-Sept. 



12. Persicaria setacea (Baldw.) Small. 

 Bristly Persicaria. Fig. 164.1. 



Polygonum setaceum Baldw. ; Ell. Bot. S. C. & Ga. 



1 : 455. 1817. 

 Persicaria setacea Small, Fl. SE. U. S. 379- 1903. 



Perennial, appressed-hirsute, stem 2°-4° high, 

 erect, simple or sparingly branched; leaves lan- 

 ceolate or oblong-lanceolate, 2'-o' long, mostly 

 short-petioled, acuminate at both ends, ciliate, 

 conspicuously pubescent on both sides, incon- 

 spicuously punctate; ocreae cylindric, long, hir- 

 sute or appressed-hirsute, fringed with very long, 

 stout bristles; racemes few, terminal, i'-2j' long, 

 erect, linear-oblong, sometimes geminate, rather 

 loosely flowered ; calyx white or pink ; stamens 8 ; 

 style 3-parted to below the middle; achene 3- 

 angled oblong or obovoid, short, thick-pointed, 

 I'-ii"" long, minutely reticulated and rather dull, 

 or smooth and shining. 



In swamps, Massachusetts and Missouri, Louisiana 

 and Florida. June-Sept. 



