PERSICARIA TRIBE 



249 



Polygonum Convolvulus 

 (Climbing Persicaria) 



3. P. convolvulus (Climbing Persicaria). 

 Stem twining ; leaves, heart - arrow - 

 shaped ; segments of the perianth bluntly 

 keeled ; fruit triangular, roughish. A mis- 

 chievous weed, with the habit of the 

 Field Convolvulus, twining round the stems 

 of corn and other plants, and bearing 

 them down by its weight. The flowers 

 are greenish - white, and grow in loose 

 axillary clusters about 4 together. Culti- 

 vated ground; abundant. Fl. July, 

 August. Annual. 



4. P. dumetorum (Copse Buck -wheat). 

 Distinguished from the last by its more 

 luxuriant growth, its winged perianth, and 

 shining fruit. By some botanists classed 

 as a variety of the last. It grows in 

 bushy places in the south of England. 

 Fl. August, September. Annual. 



5. P. viviparum (Viviparous Bistort). Stem simple, erect, bearing 

 a single, loose spike, which has in the lower part small bulbs in 

 place of flowers ; perfect flowers with 3 styles, and producing tri- 

 angular fruits ; leaves very narrow, their margins rolled back. 

 A slender plant, 6-8 inches high, remarkable for its tendency to 

 propagate itself by small, red bulbs, which supply the place of 

 flowers in the lower part of the spike ; the flowers are light flesh- 

 coloured. Mountain pastures in the highlands of Scotland, and 

 the north of England. Fl. June, July. Perennial. 



6. P. bistorta (Bistort Snake-root). A rather handsome plant, 

 with a large twisted root, and several simple, erect stems, 12-18 

 inches high, each of which bears a cylindrical spike of flesh-coloured 

 flowers ; leaves egg-shaped, the radicle ones on long stalks, and 

 sometimes as much as 6 inches long. Moist meadows, chiefly in 

 the north ; not common. Fl. June. Perennial. 



7. P. amphibium (Amphibious Persicaria). Stem erect, or sup- 

 ported in the water by the floating leaves ; flowers in oblong spikes ; 

 stamens 5 ; styles 2 ; fruit flattened ; leaves oblong, heart-shaped 

 at the base. So different are the forms assumed by this plant when 

 growing in water and on land that the varieties might well be taken 

 for two distinct species. In the water the stems are 2-3 feet long, 

 being supported by long-stalked, floating, smooth leaves ; on land 

 the stems are about a foot high, and the leaves narrow and rough. 



In both forms of the plant the spikes of flowers are rose-coloured 

 and handsome. Ditches and banks of pools ; frequent. Fl. July 

 to September. Perennial 



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