470 WILSON EXPEDITION TO CHINA 



This often misunderstood species shows a high degree of variabiHty, and it 

 seems difficult to arrange the different forms in a satisfactory way. Not being 

 able to accept the arrangement of Koidzumi, I propose to keep distinct the follow- 

 ing varieties and subvarieties which are connected more or less closely by inter- 

 mediate forms : 



Betula Ermanii, var. genuina Regel in Nouv. Mem. Soc. Nat. Mosc. XIII. 

 pt. 2, 122 {Monog. Betulac. 64), t. 2, fig. 13-28 (1861). 



Betula Ermani, var. typica Regel in Bvll. Soc. Nat. Mosc. XXXVIII. pt. 2, 

 415 (1865); in De Candolle, Prodr. XVI. pt. 2, 176 (1868). 



Betula Ermani, war. acutifolia Winkler inEngler, Pflanzenr. IV.-61, 66 (1904). 



Betula Ermani, var. communis Koidzumi in Tokyo Bot. Mag. XXVII. 149 (pro 

 parte) (1913). 



? Betula Ermani, var. sachalinensis Koidzumi, 1. c. 148 (1913). 



Gemmarum squamae basi strobilorum tantum margine ciliatae facie glabrae 

 V. sparse pilosae; bractearum lobi ciliati, ceterum glabri, laterales plus minusve 

 erecti; samararum alae interdum satis angustae. Ramuli plus minusve glandu- 

 losi, rarius fere eglandulosi, interdum initio sparse pilosi. Folia basi truncata, 

 eubrotunda, leviter cordata v. subacuta, margine satis aequahter et grosse v. 

 inaequaliter dentato-scrrata (baud distincte lobulato-serrata serraturis longe 

 acuminatis), subtus (v. utrinque) ad nervos sericea, interdum barbulata v. plus 

 minusve glabra, glandulis subtus numerosis praedita v. fere eglandulosa, nervis 

 utrinque (6-) 7-11). 



NORTHEASTERN ASIA. Kamtchatka: "inmontibus" A. Erman {type, 

 ex Chamisso); Petropavlovski, C. Wright (distributed as B . fruticosa) . Korea: 

 "distr. Musang, vallis Scgel-su, fluvium Tumingan," June 18, 1897, V. Komarov 

 (No. 487; fruits); MamiU Mt., August 13, 1906, F. N. Meyer (No. 156; resem- 

 bling var. subcordata in the serration of the leaves; fruits); Quelpaert (ex Nakai). 

 Saghalien: without locahty, Fr. Schmidt (? type of var. acutifolia) ; "in sylvis 

 Wladimirof," July 22, 1908, U. Faurie (No. 293); same place, June 1908, U. 

 Faurie (No. 291; young fruits) ; "in plateis Wladimirof," June 1908, U. Faurie 

 (No. 289; flowers); "in silvis basi montium," October 18, 1907, U. Faurie (No. 5; 

 the shape of the leaves agrees well with Erman's plate, the wings of the seeds are 

 very narrow); Soroviyofka (type of var. sachalinensis, ex Koidzumi). 



JAPAN. Hokkaido : prov. Shiribeshi, Shiribeshi-san, alt. 300-2200 m., abun- 

 dant, base to summit, July 27, 1914, E. H. Wilson (No. 7279; tree up to 23 m. 

 tall, girth 4 m., bark pale gray, smoothish; also reduced to shrub with long spread- 

 ing branches, commonly rising from thick very short base) ; prov. Ishikari, Teine- 

 san, abundant, July 31, 1914, E. H. Wilson (No. 7304; tree 13-20 m. tall, girth 

 0.6-2.4 m., bark grayish white; fruits); Sapporo, Mt. Moiwa, September 17, 1892, 

 C. S. Sargent (tree 10-13 m. tall, girth 0.5-0.6 m., white bark; fruits); prov. 

 Cshima, Hakodate, 1861, C. Maximowicz (di.stributed as B . idmifolia typica) ; prov. 

 Iburi, Mororan, August 24, 1905, J. G. Jack (fruits). Hondo : prov. Mutsu, near 

 Aomori, 1200-1500 m., October 3, 1892, C. S. Sargent. 



Betula Ermanii, var. genuina, subvar. Saitoana Schneider, n. subvar. 

 ? Betula Ermani, var. parvifolia Koidzumi in Tokyo Bot. Mag. XXVII. 148 



(1913). 

 Betzda Saitoana Nakai in Fedde, Rep. Spec. Nov. XIII. 249 (1914); in Tokyo 



Bot. Mag. XXIX. 43 (1915). 



A typo recedit foliis minoribus, circiter 3.5-5 cm. longis et 2.5-3.5 cm. latis, 

 nervis lateralibus 6-8. 



