POLYGONACEZ. 65 
segments white with a greenish stripe on the back, sometimes with the 
margins tinged with rose colour. Nut about } inch long, the point 
scarcely visible beyond the perianth. Plant light green, turning yel- 
lowish late in the year, the leaves with immersed pellucid dots, but no 
superficial glands. 
FORM IIl.—Polygonum (aviculare) vulgatum. 
Puate MCCXXIX. 
P. aviculare, Boreau, Fl. du Centr. de la Fr. Vol. II. p. 559. Norm. 1.¢. 142. 
Stem ascending or prostrate; the branches spreading or diffuse. 
Leaves oval or obovate-oval, subobtuse, about as long as the full- 
grown internodes. Ochree rather short, reddish at the base, dull 
silvery white and at length laciniate at the apex. Perianth indistinctly 
veined, white or pale red. Nut about as long as the perianth, dark 
chestnut, slightly shining. Plant bright green. 
By roadsides and in waste ground. Very common, and generally 
distributed. 
England, Scotland, Ireland. Annual. Summer, Autumn. 
Stems 3 inches to 2 feet long, more or less decumbent, with the 
internodes shorter than in P. agrestinum. The leaves are considerably 
shorter, } to 1 inch long, more attenuated towards the base, more 
obtuse, and of much brighter and clearer green. The ochrexe are 
longer and more torn. The flowers are very similar, but rather smaller. 
The nut is about the same size as in P. agrestinum, but rather longer 
in proportion to the perianth, darker chestnut, and rather more 
shining, especially on the angles. The leaves vary considerably in 
breadth ; the upper ones are narrow, but the lower are sometimes 
as broad as those of P. agrestinum, of which, however, I believe it to 
be merely a slight variety. 
FORM I.—Polygonum (aviculare) arenastrum. Bor, 
Prats MCCXXX, 
Billot, Fl. Gall. et Germ. Exsice. No. 2733. 
P. arenastrum, Bor. Fl. du Centr. de la Trans. Vol. II. p. 559. Norm. 1. c. p. 148. 
Stem decumbent or prostrate; the branches spreading, procumbent. 
Leaves oblong or oblanceolate-oblong, subobtuse or subacute, longer 
than the internodes. Ochree short, brown at the base, dull silvery 
white and at length laciniate at the apex. Perianth indistinctly veined, 
white, very rarely tinged with pale red. Nut shorter than the perianth, 
dull chestnut, slightly shining. Plant bright green. 
By roadsides in sandy districts. Common near London, in Surrey, 
VOL. VIL. K 
