POLYGONACE^. 65 



segments white with a grecnisli stripe on the back, sometimes with the 

 margins tinged with rose colour. Nut about I incli long, the point 

 scarcely visible beyond the perianth, l^lant light green, turning yel- 

 lowish late in the year, the leaves with immersed pellucid dots, but no 

 superficial glands. 



FORM II.— Polygonuni (aviculare) vulgatum. 



Plate MCCXXIX. 

 P. aviculare, Borcan., Fl. du Centi\ do la Fr, Vol. II. p. 559. Norm. 1. c. 142. 



Stem ascending or prostrate ; the branches spreading or diffuse. 

 Leaves oval or obovate-oval, subobtuse, about as long as the full- 

 grown internodes. Ochrcce 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 ochreas 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 III.— Polygonum (aviculare) arenastrum. Bor. 

 Plate MCCXXX. 



Billof, Fl. Gall, et Germ. Exsicc. No. 2733. 



P. arenastrum, Bor. Fl. du Centr. de la Trans. Vol. II. p. 559. Norm. 1. c. p. 143. 



Stem decumbent or prostrate ; the branches spreading, procumbent. 

 Leaves oblong or oblanceolate-oblong, subobtuse or subacute, longer 

 than the internodes. OchreaB 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. VIII. K 



