Distribution: From the Altai eastwards, through Siberia and northern Mongolia to 

 Kamtchatka and the Tshuktsher Peninsula, Sakhalin, North America, Greenland to 63" 

 north latitude. 



Betula humilis Schrank, Bayersche Fl. (1789) p. 421; Winkler, Betulac. in Engl. 

 Pflanzenr. H. 19 (IV, 61, 1904) p. 73; Ledeb. Fl. Ross. Ill, p. 653; Kegel, Monogr. Betulac. 

 (1861) p. 104 ex parte; Herder, PI. Radd. (1892) p. 65; Kptiji. ^ji. Ajit. V (1909) p. 

 1249; CyKaqeBi., Ht. Chct. Ch6. Eepesi. (1911) p. 208. Betula fruticosa Pallas, Fl. Ross. I 

 (1784) p. 62; Ledeb. Fl. Alt. IV, p. 246; Spach, Rev. Betulac. (1841) p. 193. Turczan. 

 Fl. BaicaL-Dahur. (1854, I) p. 403, no. 1060 ex parte. 



At Uibat, near the river Abakan; rather common in subalpine regions in the Urjan- 

 kai country, especially in swampy and peaty situations, and the like; frequent between 

 Kalna and Ust Algiac, and in peat-bogs in the Altaian. The pedicels comparatively long, 

 up to 12 mm. Taken with nearly ripe fruits in the second half of June. 



Distribution: Middle Europe, Russia, temperate portions of Asia, northwards to 

 65° 50' north latitude. 



Betula verrucosa Ehrh. Beitr. Naturk. VI (1791) p. 98; W^inkler, Betulac. in Engl. 

 Pflanzenr. H. 19 (IV, 61, 1904) p. 75. Betula alba L. Spec. PI. ed. II (1763) p. 1393 ex 

 parte; Ledeb. Fl. Alt. IV, p. 244; Ledeb. Fl. Ross. Ill, p. 650; Turczan. Fl. BaicaL-JDahur. 

 (1854, I) p. 400, no. 1056. Belula alba L. a vulgaris et y verrucosa Regel, Monogr. Betu- 

 lac. (1861) p. 17, 19; Herder, PI. Radd. (1892) p. 48, no. 201; KptM. $ji. Ajlt. V (1909) 

 p. 1247. 



Common in the lower regions of southern Siberia and the Urjankai country, along 

 the Bei-kem. Gathered with fruits in July. 



Distribution: According to Winkler, 1. c, the species is distributed over Europe, 

 Asia Minor, the Caucasus, Siberia, and northern Mongolia, northwards to about 50° north 

 latitude, eastern Asia, Japan. 



Betula pubescens Ehrh. Beitr. Naturk. VI (1791) p. 98; Ledeb. Fl. Ross. Ill, p. 651; 

 Winkler, Betulac. in Engl. Pflanzenr. H. 19 (IV, 61, 1904) p. 81. Betula alba L. g pubescens 

 Regel, Monogr. Betulac. (1861) p. 24; Herder, PI. Radd. (1892) p. 52; KptM. #.t. A.it. 

 V (1909) p. 1247. 



subspec. ovalifolia (Schneid.) Sukacz. in herb. (1916). Betula ovalifolia Rupr. in 

 Maak, Erst. Bot. Nachr. Amurl. II (1857) p. 560; CyKaieBi,, Kt Chct. Ch6. Bepe3i. (1911) 

 p. 210. Betula fruticosa Pall. /J Ruprechtiana Trautv., Winkler 1. c. (1904) p. 87. Betula 

 humilis e Ruprechtii, ^ reticulata, >/ ovalifolia Regel, 1. c. (1861) p. 51 — 52. 



Common in the Altaian, frequently in somewhat moist places, in subalpine regions, 

 to above the limit of conifers, where collected by me with ripe fruits at the end of July. 



Distribution: Eastern Siberia, northern Mongolia, Manchooria. 



198 



