*4 
REPORT ON A BOTANICAL TOUR IN SIKKIM, 1892, 
I returned to Lachung, where I halted for a week to dry the numer- 
ous specimens collected during the excursion to Tankra La, and also 
to make preparations fora journey to the Donkia Pass at the head 
of the Lachung Valley, and the most northern point 1 co’tH reach in 
Sikkim. 
We started on the 13th August, and arrived at Yeumtong the 
same day. The path runs close to the west bank of the Lachung 
river the whole distance. About half way we crossed an enormous 
landslip which had partly buried a large forest of Abies Webbiana 
and Larch, 
The interesting feature of this day ^s journey was the extensive Pine 
woods through which we travelled On the western slopes they grew 
down to the verge of the stream, and every tree was festooned with 
long gray streamers of the Lichen Usnea barbata, I was told that, 
when reduced to great straits, the Tibetans made use of this 
unpromising plant as food ; when boiled it was said to be gelatinous 
and palatable, and as nourishing and life-sustaining as beef. 
We saw many tailless rats, but I was prevented from procuring 
specimens by my desire to respect the superstitious notions of the 
Tibetans and Lepchas regarding them. I was told, with every appear- 
ance of belief on the part of my informants, that the killing of one of 
these animals was certain to be followed by storms of snow or rain 
according to the season of the year, and many instances of personal 
experience were related to me in corroboration of the fact. The 
Tibetans are reminded cf the near anprcach of winter when they 
observe these rats hdsy themselves in preparing their winter 
quarters. 
The valley is wide as far as Yakcha ; it there narrows for a con- 
siderable distance, broadening into large swampy flats intersected 
with streams towards Yeumtong. The spurs on the western flank 
are precipitous rocky and sterile, supporting vegetation only at 
their sheltered bases, but forests clothe the opposite side with the 
verdure. Every mountain mass in this region facing a southerly 
direction in the least degree is, m summer, exposed to the full force 
of the damp southerly winds laden with mist which blow' with in- 
creasing violence as the day advances, to die away only at night. 
These continuous current^ rapidly disintegrate the surface, washing 
dovvn the superincumbent earth and wearing away rocks which 
become precipices or crags of fantastic shapes. Vegetation, there- 
fore, cannot find permanant foot-hold under such circumstances, and 
its abundance is confined to the sheltered flanks where a copious 
rainfall is absorbed by the deep and fertile soil. 
The increase of 3,000 feet in elevation between Lachung village 
atld Yeumtong causes the appearaitce of many new plants along the 
