270 
THE RHODODENDRONS OE SIKKIM-HIMALAYA. 
ration. Six or seven successive ranges of 
Ibrest-clad mountains, as high as that where- 
on I stood, (8,000 feet,) intervened between 
me and a dazzling white pile of snow-clad 
mountains, among which the giant peak of 
Kinchin-junga rose 20,000 feet ahoce the 
lofty point from which I gazed ! The hea- 
ven-wai-d outline was projected against a pale 
blue sky, while little detached patches of mist 
clung here and there to the highest peaks, 
and were tinged golden-yellow, or rosy-red, 
by the rising sun, which touched those ele- 
vated points long before it reached the lower 
position which I occupied. 
" ' Such is the aspect of the Himalayan 
range at early morning. As the sun's rays 
dart into the many valleys which lie between 
the snowy mountains and Darjeeling, the stag- 
nant air contained in the low recesses becomes 
quickly heated ; heavy masses of vapour, 
dense, white, and keenly defined, arise from 
the hollows, meet over the crests of the hills, 
cling to the forests on their summits, enlarge, 
unite and ascend rapidly to the rarefied regions 
above ; a phenomenon so suddenly developed, 
that the consequent; withdrawal from the 
spectator's gaze of the stupendous scenery 
beyond, looks like the work of magic' Such 
is. the region of the Indian Rhododendrons." 
" The maximum of Rhododendrons appears 
to be in Asia, and their head-quarters are on 
the lofty ranges of the eastern Himalaya, 
where the mild and moist atmosphere is emi- 
nently suited to their habit." 
It would thus appear that a warm and 
damp climate is that naturally afforded to 
these fine shrubs ; and what is most signifi- 
cant as regards the probability of cultivating 
them in the open air in England, is this fact, 
that the winters they have naturally to bear 
are mild winters. " A certain degree of 
winter cold and perpetual humidity is neces- 
sary, but the summer heat is quite tropical 
where some of the genus prevail, and snow 
rarely falls, and never rests on several of 
those peculiar to Sikkim." In the case of 
R. Falconeri, which grows on the summit of 
Tonglo, at an elevation of 10,000 feet. Dr. 
Hooker remarks, that the temperature of the 
earth in which it grew was, in the middle of 
May, at 27 inches below the surface, where 
the roots are chiefly developed, 49° 5' at all 
hours of the day ; that of the air varied from 
50- to 60°. 
These observations, and the mean tempera- 
tures previously quoted, show, as is well re- 
marked in the Gardener'' s Journal,J.\i?it spring 
and not mid-winter is the season of trial, not 
only in the case of the Indian Rhododendrons, 
but in that of very many other half-hardy 
plants from various parts of the world, espe- 
cially from the mountain regions of India and 
South America. Comparing the figures just 
referred to, it will be seen that during the 
months of November, December, and Janu- 
ary, the difference in the mean temperatures of 
London and Darjeeling is about 4° only, and 
the same difference is indicated for the months 
of July, August, and September. On jthe 
other hand, February and May, the transition 
months between winter and spring, and spring 
and summer, show a difference of 6° ; the 
spring months of March and April, a differ- 
ence of 11° and 10° respectively ; and in au- 
tumn, too, as shown in October, the difference 
is 9°. " Here," as the journal above referred 
to observes, " we have a solution of the cause 
of our want of success in cultivating tender 
plants in the variable climate of Great Bri- 
tain : our springs are late, and cold, and 
changeable ; and while the winters and sum- 
mers of Darjeeling and London differ but 3° 
or 4°, the springs and autumns show a differ- 
ence of 10° and 12°. This accounts for the 
excitable nature and early growth of many of 
our half-hardy Indian plants, as well as the 
tendency of many such to grow to a late period 
of the autumn." 
But though we cannot hope to grow these 
fine things, except in some of the most favoured 
parts of England and Ireland, yet the dis- 
covery, and the probable speedy introduction 
of them, are matters of great horticultural in- 
terest. " It is true that plants originally ten- 
[ der will always remain tender ; and there is, 
! therefore, but small hope that we can ever 
accustom these glorious tree Rhododendrons 
to forget the earlier springs and autumns of 
Sikkim-Himalaya, and so perform all the 
necessary functions of growth within our four 
or five summer months, instead of extending 
it, as in India, over eight or nine ; but, never- 
theless, the skill of the cultivator has already 
turned to his use the valuable property of 
colour in the tree Rhododendron of Nepal ; 
and he will assuredly try, nor is he likely to 
fail, to extract from these tender kinds a still 
richer product." 
The distribution of the Rhododendrons is 
thus sketched by Dr. Hooker : — " The sub- 
Himalayan mountains are surely the centrum 
of this truly fine genus, distinguished by the 
number and variety of its species and groups, 
by the great size and eminent beauty of several, 
which form conspicuous features in the laud- 
scape over many degrees of longitude, through 
a great variety of elevations, and clothe a vast 
amount of surface. The Neelgherries, Cey- 
lon, and the Malay Archipelago, contain each 
some species which prove the affinity of their 
floras to that of the Himalaya. The same is 
the case with the great mountains of Northern 
Asia, Central, Southern, and especially Eastern 
Europe, the Ural, and Pontus. The genus 
