OF SOUTH-EAST SIKKIM. 
826 
With the exception of paludal Bpecies on the banks it has no phanero* 
gamic flora. A dak-bungalow is pleasantly situated on the slope at the 
north end and formed a most convenient centre for my subsequent opera- 
tions. The route is now little used as the Dzalep La is a more direct 
road for the Chumbi Y alley. The number of storehouses and huts is a 
reminder of the Tibet expedition when the place had a transient import- 
ance. Now it is one of the moat desolate posts in Sikkim. The 
Chumbi boundary at the Nathui La lies about eight miles to the east. 
Changu and its lake lie in a hollow girt by irregular ridges which 
rise to 14 — 15,000 feet. In the valley basin there is a fair extent of what 
maybe termed coarse meadow, where Banunculacece Frimulacea 
are much more ‘prominent however than GraminecR. The slopes above 
are in most places covered with Ehododendrons, but here and there are 
open spaces cleared by shepherds. These extend in places to the top 
of the ridges and afford a very varied pasturage of herbs and prostrate 
shrubs. 
On the 6th we climbed the hills lying to the west which do not rise 
above 14,000 feet. The slopes soon becfome rocky and barren. The limit 
of vegetation and the absolute altitude reached by typical individual 
species seem to be lower here than in other parts of Sikkim. In tlie 
Zemu and Llonakh valleys similar plants range at least 1,000 feet 
higher, but these latter valleys are drier than those of south-east 
Sikkim and the surrounding sheltering mountains much loftier. Thus 
in Western and Northern Sikkim an altitude of 15,000 feet gives a con- 
spicuous and varied flora, while a height of 15,000 feet in the Changu 
area is usually a crest of bare rocks exposed to the force of the rains, 
80 that the altitude reached by prevalent alpines in this area is much 
lower in many cases than what is recorded in the flora of British India, 
as a glance at the appended Ijst will show. The snow must lie long on 
these Chola hills, melting slowly in the prevailing mists, and thus various 
conditions combine to give the alpine flora an exceedingly short flowering 
season. 
The most tenacious phanerogams on the upper rocks and sometimog 
the only ones I found were Primula muscoides and Clirysosjplenium car- 
nosum. Minute forms of Cochlearia, Arenariai Potentillay Saxi/raga and 
Polygonum occur sparingly on the wind sw^ept crests. From 12 — 13,000 
feet the vegetation was in early July in full bloom. The tall Gentiana 
stylophora and 8wertia Hooheri were very conspicuous. Rheum nohiU 
was scarce, appearing at 13,500 feet, which is comparatively low for it. 
Primula was especially prevalent with a dozen fine species. The largo 
species of Senecio of the section Ligularia were just coming into bud and 
formed a considerable element in the vegetation. As everywhere in 
B 2 
