71 



upper joints of the stem are covered with a very long sheath. 

 The style is cleft or forked towards the top, so that some bota- 

 nists describe it as two styles joined together half-way up\ 

 There is seldom more than one spike of flowers on a stem, and 

 that at the end of it. 



SPOTTED PERSICARIA. Polygonum persicaria. 



Plate 5, fig. 7. 

 Stamens six. Style one, forked. Spike oblong, 



Frequent on moist ground, flowering in July and August, 

 growing upright and branched, one or two feet high. The leaves 

 are either sessile, or with very short stalks, lanceolate, quite 

 smooth, entire on the edges, and often spotted with a dark 

 color. The spikes of flowers are dense, rose-colored or greenish, 

 oblong, stalked, numerous, and growing out of a short yel- 

 lowish sheath, fringed with hairs. Style as in the last. 



PALE FLOWERED PERSICARIA. Polygonum lapathifolium. 



Plate 5, fig. 8. 



Stamens six. Styles two, distinct. Leaves ovate, lanceolate. 

 This plant, which grows abundantly on waste ground and 

 dunghills, is rather difficult to distinguish from the last, be- 

 cause it varies much in appearance. Sometimes the leaves are 

 similarly spotted, but they are wider in proportion and more 

 stalked. The flowers are paler in color. The whole plant 

 larger and often somewhat hairy. The stipules or sheaths are 

 without hairs, and above all, there are in this species two distinct 

 styles. 



BITING PERSICARIA. Polygonum hydropiper. 



Plate 5, fig. 9. 

 Stamens six. Style one, forked. Leaves lanceolate. 



In flower in the autumn on river banks and all damp places. 

 Known at once by its very long, slender, somewhat drooping 

 spikes, of reddish distant flowers. The leaves are of a pale 

 green, lanceolate, sharp pointed, almost without stalks, and a 

 little waved at the edges. 



O. S. Bistort or Snake-weed, Viviparous Bistort, Roberts's Knot-Grass, 

 Sea-side Knot-Grass, Buck Wheat, Copse Buck Wheat, all belong to the 

 first section ; Lax Flowered Persicaria, and Small Creeping Persicaria to 

 the second section. 



