826 
TEE ALPINE AND SUB ALPINE VEGETATION 
temperate and alpine Sikkim there were miles of Rhododendron, the 
more alpine species being still in flower. Trees occurred in the more 
sheltered corners. Two miles above Chaugu^ and also just below the 
lake, were forests of Abies IFehbiana. Unfortunately many of the trees 
were dead, as during the Tibetan expedition their lower bark was freely 
stripped oS by the host of coolies employed for the carriage of supplies 
and used by them for shelter against the monsoon deluges. So now 
between Laghep and Changu are scores of naked giants tottering in 
decay. No other trees were here the rivals of the Abies in height or 
girth. AceTf Frunus, EosUf FiruSy Viburnum, Betula, 8alix were 
present in stunted forms. 
The herbaceous flora was at its best and I secured many interesting 
species. A rare Fotentilla (F. sikhimensis Train) allied to F. purpurea 
was found on the dliffs about 13,000 feet, and by the lake another new* 
Swertia (S. Burk Uliana.) \ in shady rocks by the stream a new Arenaria 
(A. Balfouriana)', Loxostemon pulchellus appeared here and there but 
never in quantity. "Ripe fruit of this I have never been able to secure, 
the plant being difficult to find late in the year. The fruit would be of 
interest as the position of the genus is still somewhat doubtful. I 
noticed the occasional presence of bulbils in the axils of the leaves ; 
these are ovoid, apiculate, 8—12 together, and are possibly homologous 
with the clustered mass of bulbils at the root. 
After two days given to the flora round Changu, we ascended on the 
9th of July to the Nathui La. The pass is a very easy one to surmount 
and can l)e reached within two or three hours from Changu. The eleva- 
tion is 14,250 feet. The vegetation at the top of the ridge was but little 
different from what I found at 13,000 feet. The more conspicuous plants 
were Caliha scaposa, Cochlearia scapijlora, Fotentilla SibbaUH, P. pedun~ 
cularis, F. microphylla, Saussurea sps., Bkododendron campanulatum, 
B. anthopof/on, li. lepidotum, Cassiope fastiyiata, Frimula ohtusifolia, 
P. 8tnartii, P* pusilla, F. sapphirina. 
T wo days were given to the area south of Changu including Laghep. 
Among the more interesting plants was a Cardamine which is, I believe, 
Cardamine Griffithii. Griffith's original specimens from Bhutan have 
no flowers but the vegetative parts agree. It is a more delicate plant 
than Cardamine macrophylla and makes a better ^ cress.^ So few alpine 
species are edible that this one is worth noting in a land where vege- 
tables are scarce. Rheum acuminatum, Rheum nohile and Smilacina 
oTeracea are also worth attention from this point of view. Species of 
Arisnema were plentiful at Laghep but edible only by the greatly 
daring. 6enecio Kingianus, a fine new species about three feel high, was 
also abundant to the south of Changu associated with S, Mortonu 
