The path ran N.N.W. for two miles, and then crossed the Lachen above its junction with the Nunee* [I suspect there is a pass by the Nunee to the sheds I saw up the Zemu valley on the 2nd of July, as I observed yaks grazing high up the mountains: the distance cannot be great, and there is little or no snow to interfere.] from the west: the stream was rapid, and twelve yards in breadth; its temperature was 48 degrees. About six miles above Tungu, the Lachen is joined by the Chomio-choo, a large affluent from Chomiomo mountain. Above this the Lachen meanders along a broad stony bed; and the path rises over a great ancient moraine, whose level top is covered with pools, but both that and its south face are bare, from exposure to the south wind, which blows with fury through this contracted part of the valley to the rarified atmosphere of the lofty, open, and dry country beyond. Its north slope, on the contrary, is covered with small trees and brushwood, rhododendron, birch, honeysuckle, and mountain-ash. These are the most northern shrubs in Sikkim, and I regarded them with deep interest, as being possibly the last of their kind to be met with in this meridian, for many degrees further north: perhaps even no similar shrubs occur between this and the Siberian Altai, a distance of 1,500 miles. The magnificent yellow cowslip (_Primula Sikkimensis_) gilded the marshes, and _Caltha,_* [This is the _C. scaposa,_ n. sp. The common _Caltha palustris,_ or "marsh marigold" of England, which is not found in Sikkim, is very abundant in the north-west Himalaya.] _Trollius,_ Anemone, _Arenaria, Draba,_ Saxifrages, Potentillas, Ranunculus, and other very alpine plants abounded. At the foot of the moraine was a Tibetan camp of broad, black, yak-hair tents, stretched out with a complicated system of ropes, and looking at a distance--(to borrow M. Huc's graphic simile)--like fat-bodied, long-legged spiders! Their general shape is hexagonal, about twelve feet either way, and they are stretched over six short posts, and encircled with a low stone wall, except in front. In one of them I found a buxom girl, the image of good humour, making butter and curd from yak-milk. The churns were of two kinds; one being an oblong box of birch-bark, or close bamboo wicker-work, full of branched rhododendron twigs, in which the cream is shaken: she good-naturedly showed me the inside, which was frosted with snow-white butter, and alive with maggots. The other churn was a goat-skin, which was rolled about, and shaken by the four legs. The butter is made into great squares, and packed in yak-hair cloths; the curd is eaten either fresh, or dried and pulverised (when it is called "Ts'cheuzip").