PERSICARIA FAMILY 419 



branched ; leaves lanceolate, flat, with minute warts, often with a 

 purplish-black blotch in the centre, more or less hairy on both 

 sides ; stipules loose, much fringed ; -flowers in a short, dense, 

 erect, cylindrical spike, red or white ; peduncle smooth ; stamens 

 5 — 8 ; styles 2 — 3, united for half their length. — Waste and damp 

 ground ; abundant. — Fl. July — October. Annual. 



10. P. lapathifolium (Pale-flowered Persicaria). — A closely allied 

 species ; stem sometimes red or spotted, swollen at the nodes ; 

 leaves lanceolate, acuminate, smooth or downy, sometimes with a 

 black blotch above, or glaucous below ; stipules close to the stem, 

 with little or no fringe ; flowers pale, in axillary or terminal, 

 cylindric spikes ; peduncle rough ; stamens 5 — 6 ; styles 2, dis- 

 tinct. — Waste and damp places ; common. — Fl. July — September. 

 Annual. 



11. P. maculdtum (Spotted Persicaria). — Smaller than the pre- 

 ceding, often prostrate, with very thick nodes ; leaves lanceolate, 

 tapering much at both ends, wavy, generally blotched, white and 

 woolly beneath, with loose, shortly fringed stipules ; spikes some- 

 times interrupted ; peduncle rough ; styles connected below. 

 — Damp gravelly places ; not common. — Fl. July — September. 

 Annual. 



12. P. amphibium (Amphibious Persicaria). — Assuming such 

 different forms when growing in the water and on land that they 

 might well be taken for two distinct species. It has a slender, 

 woody, branched rhizome creeping in the mud, with branches about 

 a foot high and erect, if on land, with sub-sessile, lanceolate hairy 

 leaves, or with floating stems 2 — 3 feet long, if on water, supported 

 by long-stalked, floating, oblong, smooth leaves; flowers rose- 

 coloured, in handsome oblong spikes ; stamens 5, with exserted 

 anthers ; styles 2, united for half their length ; fruit flattened. — 

 Ditches and banks of pools ; common.— Fl. July — September. 

 Perennial. 



**** pi an ts with rhizomes ; erect, unbranched stems ; terminal, 

 spike-like racemes ; stamens 8 ; styles 3 ; nut 3-sided 



13. P. Bistorta (Bistort, Snakeweed, Snake-root).— A rather 

 handsome plant, with a large, woody, twisted rhizome, and several 

 erect, simple stems 1 — 1\ foot high; leaves ovate, the radical ones 

 on winged petioles and glaucous beneath ; flowers pink, in terminal, 

 cylindrical, dense spikes. — Moist meadows ; frequent. The 

 English names Bistort (twice twisted) and Snake-root allude to the 

 form of the rhizome. It forms large circular patches in meadows, 

 and also occurs in old-fashioned gardens, where its astringent 

 rhizome was once grown as a medicine. The green shoots are 



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