BETXJLACEAE. — ALNUS 499 



Alnus sihirica, var. paucinervia Callier, I. c. 891, fig. 557 h (1912). 

 Alnus sihirica, var. tinctoria Koidzumi in Tokyo Bat. Mag. XXVll. 145 (forma 

 a-e inclusa) (1913). 



NORTHEASTERN ASIA. Transbaikalia: "ad fl. Argun," 1833, AT. Twrc- 

 zaninow (? type of A. sihirica; co-type in Herb. Gray). Mandshuria: meadow- 

 near Sryetinsk, August 13, 1903, C. S. Sargent (sterile; branchlets and petioles 

 finely pubescent or tomentose); mountain streams 12 hours east of Harbin by 

 railway, August 31, 1903, C. S. Sargent (fruits). Amur: "ad fl. Amur," 1855, 

 jB. Maack (No. 611; sterile, branchlets and petioles tomentose, leaves rather 

 glabrous); Amur, C. Maximowicz (fruits; pubescence as in No. 611); "Amur 

 superior et medius," August 28, 1891, S. Korshinsky (fruits; less hairy than the 

 foregoing specimen). Ussuri: near Vladivostok, common, August 18, 1903, 

 C. S. Sargent (small tree; sterile). 



JAPAN. Hokkaido: prov. Oshima, Hakodate, Oiwagi, 1861, C. Maximowicz 

 (fruits). Hondo: prov. Shimotsuke, around Nikko, common, on way to near 

 Kieifuri waterfall, October 23, 1914, E. H. Wilson (No. 7711; tree up to 12 m. 

 tall, girth 0.9 m.; fruits); prov. Rikuchu, Hayachine-s.an, side of streams, etc., 

 common, September 27, 1914, E. H. Wilson (No. 7553; tree 13-17 m. tall, girth 

 0.6-1.2 m.; bark smooth, gray, branches long, fairly slender, horizontally spread- 

 ing; fruits); prov. Shinano, Otake-gawa, mountain slopes, common, October 31, 

 1914, E. H. Wilson (No. 7751; bushy tree, 7-12 m. tall, girth 0.6-0.75 m., fruits); 

 Ontake, 1905, U. Faurie (No. 6646; fruits); prov. Shimosa, Matsudo, August 11, 

 1901, February 15, 1905 (ex Herb. Sakurai; sterile and flowers); prov. Musashi, 

 Tokyo, March 11, 1905 (ex Herb. Sakurai; flowers); prov. Suraga, slopes of 

 Fuji-san, abundant, from alt. 600 m. upwards, May 8, 1914, E. H. Wilson 

 (No. 6646; small tree, 4-10 m. tall, bark smooth, gray; female flowers, young 

 leaves); prov. Sagami, Hakone, common, April 17, 1914, E. H. Wilson (No. 

 6435; tree 7-12 m. tall, girth 0.3-0.9 m., branches ascending-spreading; flowers 

 and old fruits); prov. Kozuke, round Karuizawa, woods, August 31, 1914, 

 E. H. Wilson (No. 7428; slender tree, 7-10 m. tall, girth 0.3-0.45 m.; fruits); 

 prov. Mutsu, Lake Towada, common, alt. 300-600 m., October 4, 1914, E. H. Wilson 

 (No. 7608; tree 10-13 m. tall, girth 0.3-0.75 m.; sterile). 



I refer to var. sihirica all those forms which have glabrous or nearly glabrous 

 branchlets, peduncles and petioles, and the leaves hairy below only on the midrib 

 and veinlets. But there are several specimens mentioned above which are inter- 

 mediate between this variety and the typical A . hirsuta. In the type the branchlets, 

 peduncles and petioles are more or less hirsute or tomentose, while the leaves are 

 covered beneath with a brownish tomentum or, if glabrescent, are mostly hairy 

 also between the veinlets. I do not see how it is possible to keep the true. A. 

 sihirica ' distinct from A. tinctoria of Komarov, Callier and Nakai. The last two 

 authors distinguish several varieties which certainly need further investigation. 

 Leaves from different parts of the same tree sometimes show a good deal of varia- 

 tion in shape, texture and pubescence, so that it is very difficult to describe 

 varieties or forms only from scanty herbarium specimens. There are, I am sure, 



' In the co-type in Herb. Gray the leaves are round-ovate, sometimes somewhat 

 cordate at the base, obtuse at the apex and obtusely lobed at the margin. On the 

 upper surface they are pubescent only on the midrib, while on the under surface 

 also the principal veins and even some veinlets are more or less hirsute, but be- 

 tween the veinlets they are wholly glabrous. The ends of the branchlets, the base 

 of the peduncles and the petioles are more or less finely tomentose. The leaves 

 are up to 8.3 cm. long and 8 cm. broad. The specimen is very imperfect. 



