l'oly}<()iuiin vivipiiiuiii 1,. S\k\\ 1*1. eel. II (17(12) |). '}U\: Ledcb. Fl. All. 11, p. 78: 

 'rurc/aii. Cat. Haical. no. <JG6; Lcdcl). IL Ho.s.s. Ill, p. .")1',); Turczan. 1"1. Baical.-Daluir. 

 (1852, IV) p. 1,')1, no. 1)77: Mfi.siu'r, Moiio^r. (icn. I'nliif/. (182(j) p. 52, no. 5; Meisner, 

 Poli/g. Ilaule-Asie, p. 3-17, no. l!!; Ih-idrr, 1*1. Kadd. (18112) p. 210. no. 8."): i.'in.i.i. <l«.i. 

 A.iT. V (1909) p. 1161. 



Ihi.s species, beinn \i'iv conunon in nioisl meadows on die islets in llie river.s 

 Yenisei iwid .Miakan. in die .\niyl lai^a, and the I'ljankai eounli v. varies considerably 

 in size and liaiiilus. iii-eadlli of leaves, etc. Tlicic aic lo be I'oiiiid forms in wliich the 

 leaves are cpiite smootii nndeinealb. and others willi the under side of the leaves rather 

 densely pubescent. There arc, however, between the various forms, marked intermediates. 



On islets in the river Abakan, near Askys, I have collected a vigorous form, from 

 40 to 45 cm. higli. with narrow, lanceolate, long-petioled radical leaves, to 12 cm. long, 

 and 25 cm. broad. I'lolialily belonging to f. i-loiuitihnn I'.ick in l>i:ic.nKNii. Icon. XXIV 

 (190()) p. 81. Similar vigorous forms, with broader radical leaves, are common in the 

 Urjankai country, and abundant, for instance, between the Algiac Pass and L'sl Algiac, 

 as well as on the Kanisaia. 



In the Altaian, at an allilude of about 2(X)0 m. above sea-level, I have collected a 

 slender form, with (juite smooth and very narrow leaves, onlv 0,;5 — 0,5 cm. broad. 



Distribution: Europe, and arctic islands, Caucasia, south-western and central 

 Asia. Siberia, northwards to Taimyr (75° north latitude), northern Mongolia, eastern 

 Asia, Sakhalin. North America. Greenland. 



Polygonum Bistorta L. Spec. Pi. ed. II (1762) p. 516; Ledeb. Fl. Alt. II, p. 77; 

 Turczan. Cat. Baical. no. 965; Karel. et Kiril. Enum. PI. Fl. Alt. no. 783; Ledeb. Fl. 

 Ross. Ill, p. 518: Turczan. Fl. Baical. -Daiiur. (18.52, IV) p. 150. no. 976: Meisner, Monogr. 

 Gen. Poh]g. p. 51; Herder. PI. Radd. (1892) p. 215. no. 86: h>i,i.i. <l>.i. A.n. V (1909) 

 p. 1160. 



Common in moist meadows, and on river-banks in the lower parts of the river 

 Abakan, as well as near Kushabar, Ust Algiac and I'st Sisti-kem. Collected with flowers 

 at Ust Abakan at the end of June, and with ripe fruits at Kushabar, about the middle of 

 July. The specimens belong to f. lalifolium H.\v.\i;, Arzney-Gew. V (1817) p. 19. 

 Poli]gonum bislorla a vulgaris Meisner, 1. c. 



Besides, I have collected, near Kushabar, some specimens of a vigorous form, 

 especially characteristic in having the under side of the leaves of a rusty brown colour. 

 These specimens, therefore, are probably identical with specimens reported by I.KnEHorK 

 in Fl. Boss. III. ji. 519 ufoliis laliorihiis. siiblus parciiis pilosis siibfernigineis: pills stib- 

 nifis. — In proi'iiiciis Caucasicis et Iciris boreali-orienlalibiis.» The form in cpieslion 

 has the leaves underneath wholly and densely pubescent, of a rusty lirown colour, giving 

 the under side of the leaves a dark brown, frequently nearly felted or velvet-like appea- 

 rance. I separate this characteristic form, the distribution of which seemed to be confined 

 to easterly regions, as 



205 



