578 POLYGONUM. tcLAss vm. order ii. 



**** Helcine. De Cand. Flowers in axillary fascicles. Style 

 single, from one to three lobed stigmas. 



12. P. Convolvulus, Linn. (Fig. 658.) Climbing Buck-wheat. 

 Stem twining, angulato-striated ; leaves covdato-sagittate, the three 

 inner segments of the perianth ohtusely keeled ; nuts triangular, opaque, 

 black. 



English Botany, I. 941. — English Flora, vol. ii. p. 239. — Hooker, 

 British Flora, vol. i. p. 186. — Lindley, Synopsis, p. 212. 



Root small, tapering. Stem climbing, much branched, twining 

 itself around other plants near it, somewhat angular from the nume- 

 rous prominent stria, and roughish, of a dull green, leafy, from two to 

 five or six feet long. Leaves alternate, heart-shaped, with the lobes at 

 the base pointed in an arrow-shaped manner, the margin mostly waved 

 and roughish, a dull green above, paler beneath and roughish, with a 

 mid-rib and branched lateral veins, the footstalks rather long, striated, 

 and channeled above, having an uneven somewhat membranous 

 stipule at the base. Inflorescence axillary clusters, of about four 

 floivers, each on a short stalk, the perianth cleft half way down into 

 six ovate concave segments, of a palish green colour, the three outer 

 ones larger, with a more or less winged keel, the three inner ones with 

 an obtuse keel. Stamens eight, sometimes only six, the filaments 

 simple, awl -shaped, about half as long as the perianth, the anthers 

 small, yellow, roundish. Style very short, with a three-cleft stigma. 

 Fruit an acutely triangular ovate nut, smooth, of an opaque black 

 colour, as long as the perianth, and enveloped in it. 



Habitat. — Corn fields, gardens, &c. ; frequent. 



Annual ; flowering from June to September. 



This in many parts of the country, especially in sandy districts, is a 

 very troublesome weed amongst corn. It produces a great number of 

 seeds, which are the food of many birds, possessing considerable 

 nutritive properties, though much less than the following species. 



***** Fagopyrum. Tournef. Flowers racemose, the racemes pani- 

 culated, or corymbose. Styles three, with thickened capitate stigmas. 



13. P. Fagopy'rum, Linn. (Fig. 659.) Buck-wheat. Stem nearly 

 erect, without prickles; flowers in simple axillary racemes, and ter- 

 minal corymbose clusters; leaves cordato-sagitiate; nuts triangular, 

 with even angles. 



English Botany, t. 1044.— English Flora, vol. ii. p. 239. — Hooker, 

 British Flora, vol. i. p. 186. — Lindley, Synopsis, p. 212. 



Root tapering, with fibrous branches. Stem erect, about a foot high, 

 succulent, branched, somewhat zig-zag, leafy, smooth, except a hairy 

 line on one side, and slightly striated. Leaves smooth, dark green, 

 paler on the under side, with a mid-rib and branched lateral veins, the 

 upper ones nearly sessile, the lower on channeled footstalks, with short 



