THE ALPINE AND SUB^ALPINE VEGETATION OF 
SOUTH-EAST SIKKIM. 
r. r. Smith, 
INTRODUCTIOl^. 
The writer was deputed in July — August 1910 by Major A. T. Gage, 
I.M.S., Director of the Botanical Survey of India, to explore botanically 
South-East Sikkim, more especially the ridges lying between the Cho-La 
and the Tanka-La. Both these passes were visited by botaijist many 
years ago, by the late Sir Joseph Hooker and the late Mr. C. B. Clarke, 
and more recently (1892) by Mr. G. A. Gammie. However the interven- 
ing country, a tangle of hills with deep wooded valleys, was unknown 
and offered an inviting field for investigation. The area is one of the 
wettest in the Himalayas, exposed to almost the full force of the monsoon 
rains. During July and August it rained every day, often all day and 
generally the greater part of every day. The actual total of inches is 
probably less than wJiab is received on the outer hills below and at 
Darjeeling, as owing to the elevation the rain is frequently more of a 
drizzle than a downpour, but the amount of sunshine during the short 
flowering season is very limited. The conditions approximate to those 
of the Singalela Range with less violent winds. 
I left Darjeeling on June 29th with Lepcha collectors and coolies 
travelling via Namchi, Temi, Song and Gangtok. As the Chola Range 
is practically without settled inhabitants, there being only a few herds- 
men during the summer months, airangements were made at Gangtok, 
the capital of Sikkim, for food supplies. Gangtok was left on July 3rd 
by the Changu road which leads to the Kathui La, one of the chief 
passes into the Chumbi V alley. The greater part of this road was 
surveyed and completed for the Tibet expedition of 1903-04 as a means 
of relief to the Dzalep-La (Jdep La) route and is an excellent one 
throughout, presenting little difficulty beyond the climb of 10,000 feet 
in a journey of about 30 miles. The first march is to the Karponaag 
bungalow, a gradual rise from 5,000 to 9,000 feet. The forest vegetation 
corresponds closely to that of the Darjeeling District at the same eleva- 
tion. Signs of cultivation soon disappear and at Karponang there are 
only a few huts near the bungalow. It is not an area to attract the 
