BALFOUR—NEW SPECIES OF RHODODENDRON. 297 
bloom. . . . The latest authority doubles Rh. argenteum 
up with Rh. grande which, with all humility, I am prepared to 
show is quite distinct.” Elsewhere in the current literature of 
the day Mr. Mangles gave expression to his view—and here 
may I ask is there no enthusiast who will bring together and 
publish the writings upon Rhododendrons by Mr. Mangles which 
are scattered through horticultural periodicals? A valuable 
work it would be—that geographical variation in these Hima- 
layan types to the extent of specific difference is a feature of the 
genus. In one striking passage he says’: “ As the Himalayan 
range passes eastward through Nepal, Sikkim, and Bhutan, the 
genus Rhododendron becomes truly protean in form and presents 
not only an extraordinary number of species in a small space 
but also striking geographical varieties in very great abundance.’ 
To him Rh. argentewm, Hook. f. is the Nepal and Sikkim form > 
which finds its representative through Bhutan in Rh. grande, 
Wight and also in Rh. longifolium, Nutt. in the same way 
as in Rh. Falconeri, Hook. f. and in Rh. Thomsont, Hook. f. 
there are to be observed western and eastern forms. The 
basal soundness of the opinion is borne out by later discoveries 
of representative forms of the earlier known Himalayan species 
so far to the eastwards as Yunnan. 
Upon the question of the degree of difference between Rh. 
grande, Wight, Rh. argenteum, Hook. f., and Rh. longifolium, 
Nutt. nothing of moment can be added as yet to the evidence 
available to those who in the past have extracted from it the two 
divergent conclusions which have been stated. And this must 
remain the position until we obtain more material from Bhutan. 
Amongst the specimens which have already come to Edinburgh, 
presented by Mr. Bulley from the collecting of Mr. R. E. Cooper 
in Bhutan, is one of a Rhododendron in fruit which belongs 
without doubt to this series, and we will hope that the spoil of 
Mr. Cooper’s further exploration will include additional speci- 
mens bearing upon the problem. As Mr. Cooper is primarily 
collecting seeds the dried specimens he sends are mostly of 
fruiting plants, and therefore some years must elapse before 
the plants raised from his seeds will supply satisfactory proof 
of their identity. I myself am inclined to the view expressed 
by Mr. Mangles, and expect that when we do get to know 
the Rhododendrons of Bhutan we shall find that the type 
which in Sikkim is Rh. argentewm, Hook f., in Bhutan shows 
differences in more than one direction, which justify separate 
nomenclature of microforms or species under the names Rh. 
grande, Wight, Rh. longifolium, Nutt., and probably others. 
Meanwhile to come to something more precise, I have to 
2 Gardeners’ Chronicle, n.s., xvii (1882), 295. 
