POLYGONUM. OCTANDRIA. TRIGYNIA. 405 



ceding species. Perianth white or pale red. Styles slightly 

 exserted. A''ut broad-ovate, compressed, obscurely triangular. 

 Hab. Along ditches and in swamps ; rare. August. 



11. P. Persicaria L.: flowers hexandrous ; styles bifid; 

 spikes ovate-oblong, erect ; peduncles smooth ; leaves lanceo- 

 late ; stipules smooth, ciliate. W ill d. Spec, II. p. 446. 

 Smith Fl. Brit. I. p. 424. Eng. Bot. i. 736. M i c h. 

 Fl. I. p. 239. P M r s A F/. I. p. 27 1 . B i g. Bost. p. 94. 

 Persicaria mitis vulgaris, &;c. Cold. JN'oveb. 91. 



Root annual. Stem erect, branched, I — 2 feet high, smooth, 

 often of a reddish colour. Leaves on very short petioles, 

 smooth, the upper surface often marked with a dark coloured 

 binate spot. Sfiikes terminal, dense. Flowers rose-colour. 

 A''ut compressed, triangular. 



Hab. In low grounds and along ditches ; very common. 



Black-heart. — Ladies' -thumb. 



12. P. orientale L. : flo^yers heptandrous, digynous ; 

 leaves ovate ; stem erect ; stipules hairy, hypocrateriform. 

 Wind. Spec. II. p. 448. Bot. Mag. 213. Pursh FL 

 L p. 272. Elliott Sk.L^, 251. 



Root annual. Stem 3 — 5 feet high, branched, pubescent. Leaves 

 very large, petiolate, acuminate, minutely pubescent. Stifiules 

 tubular, with the border spreading or reflexed, ciliate. Sfiikes 

 numerous, subpaniculate, crowded, a little nodding. Flowers 

 large, bright rose-colour. JK'ut compressed, broader than long. 



Hab. In cultivated grounds and on road sides; naturalized in 

 many situations. August — September. 



* * * Flowers in fianiculate sfiikes ; fierianfh 5-leaved. 



Polygonella. 



13. P. articulatum L. : flowers perfect, octandrous, tri- 

 gynous, nodding ; spikes paniculate, filiform ; pedicels soli- 

 tary, articulate near the base ; bracts imbricate ; leaves 

 linear; nut triquetrous. Willd. Spec. II. p. 450. Pursh 

 Fl. 1. p. 272. Jfutt. Gen. T. p. 255. 



Root annual. Stem about a foot high, erect, branched above, 

 smooth. Leaves linear, three-fourths of an inch long, obtuse. 

 Stifiules short, naked, truncate. Sfiikes or racemes erect, ter- 

 minating the branches ; fiedicels longer than the flowers, ca- 

 pillary, distinctly articulate near the base; bracts short, trun- 

 cate, approximate or imbrical, thus giving the spikes a 

 jointed appearance. Perianth spreading, rose-colour ; leaflets 

 broadly obovate. Stamens shorter than the perianth ; anthers 

 simple. Stigmas capitate, nearly sessile. JVut acutely trian- 

 gular, acuminate. 



Hab. In barren sandy woods. Plentiful in the pine barrens of 

 New- Jersey. V^ery abundant on the sandy plains west of Al- 



