982 The Trees of Great Britain and Ireland 



acute at the apex, and two or three times as long as the divergent short rounded 

 lateral lobes ; nutlets with narrow wings. 



This variety is represented in Kew Gardens by two trees obtained from St. 

 Petersburg in 1891 and 1894, and 25 feet and 20 feet high respectively. It is very 

 distinct in appearance from the typical form of the species, having white bark ; 

 smaller, few -nerved, thinner leaves; and different catkins. Moreover, the 

 branchlets and fruiting peduncles are shortly pubescent in the variety, and 

 tomentose in the type. 



This variety,^ judging from the material in the Kew Herbarium, is common in 

 the Himalayas, and probably constitutes a distinct species, which a careful study in 

 the field may show to occupy a different area of distribution from that of typical 

 B. utilis, which is so readily recognisable by its reddish bark and other 

 characters. 



Distribution 



B. utilis'^ \5 widely distributed in the Himalayas and in China. It occurs in 

 West Tibet, and in the Himalayas from the Kurram valley and Kashmir, to Sikkim 

 and Bhotan, at altitudes usually ranging from 10,000 to 14,000 feet, but descending in 

 the north-west to 7000 feet. It is often gregarious at the upper limit of arborescent 

 vegetation, where it is commonly associated with Rhododendron campanulatum. 

 According to Brandis, it attains 50 to 60 feet in height, and sometimes 10 or 12 feet 

 in girth. Gamble's account of the bark includes that of the type and of var. 

 Jacquemontii ; as he describes it as smooth, shining, reddish white or white, the 

 outer bark consisting of numerous distinct, thin, papery layers, peeling off in broad 

 horizontal rolls; the thicker lower part of the bole becoming rough and dark as in 

 the European birch. He states that the growth is slow, with an average of fifteen 

 rings per inch of radius. The wood is extensively used in the inner arid Himalayan 

 region for building purposes ; it is elastic, does not warp, and seasons well. The 

 bark is the most valuable part of the tree, and is used for paper, umbrellas, hookah- 

 tubes, and roofs of houses. 



In China it is a moderate-sized tree, growing only at high elevations, between 

 8000 and 13,500 feet, in the provinces of Szechwan, Hupeh, and Kansu. It was 

 seen in the latter province by Przewalski,^ who describes the bark as reddish, 

 peeling off and hanging from the tree in long festoons. 



This species is very rarely seen in cultivation, and the typical form from the 

 Himalayas, like most of the broad -leaved trees from that region, for some un- 

 explained reason, does not appear to have succeeded in this country. At Grays- 



1 Shirai, in Tokyo Bot. Mag. viii. 320, ff. 23, 24 (1894), states that this variety occurs in Japan ; but the plant figured 

 by him seems to be identical with a specimen gathered by Maximowicz in the province of Shinano, and labelled B. 

 Bhojpattra, var. typica, Kegel, which is certainly not that species, and appears to be B. ulmifolia, S. et Z. Shirai's account 

 of the bark of this tree, as not being papery, but greyish brown, smooth, cracking, and falling off in patches, confirms this 

 identification. 



2 There is no evidence that B. utilis occurs in Japan, where it is represented by the closely allied species B. Ermani. 

 Shirasawa, in Icon. Ess. Forest. Japon, text 44, t. 23, ff. 9.22 (1900), figures a tree as B. Bhojpattra which is not this 

 species (B. utilis), as is confirmed by his account of the bark, as being hard, compact, and falling off in scaly facets. 

 B. Ermani, var. nipponica, has also been considered erroneously to be a form of B. utilis. 



3 Cf. Bretschneider, Europ. Bot. Discoveries, 987 (1898). 



