A BOTANICAL TOUR IN S1KKIM. ' 207 



radiating leaves pressed closely to the soil. Rheum nobile is visible on the 

 faces of all the cliffs around, and ascends to 17,000 feet. 



Our third day's camp was pitched below the ascent to Kanko La, which 

 passes at the gorge, cut by the river through a low line of cliffs, forming a 

 barrier across the head of the Tankra Choo Valley. 



The next day we crossed this by the frequented path, and followed the 

 track to the Tankra Pass, which is at an elevation of 16,000 feet. The ter- 

 minal valley slopes gently to the pass, is exceedingly rocky, and is bounded 

 by snowy ridges ] and much snow lay in its hollows. ' The rounded surface 

 of the pass is a conglomeration of sand and boulders which are constantly 

 sliding down from the crags on either side. 



On the Tibetan side, a narrow grassed valley descends steeply. Fog 

 effectually prevented a more extended view. Between the Kanko La and 

 the barren glacier below Tankra La there was a multitude of bright-hued 

 flowering plants. Brown and yellow Chrysosplenium, yellow Saxifrages, blue 

 and yellow forms of Corydalis, a few species of Pedieularis, beautiful small 

 primroses — P.uniflora, P. muscoides and P . soldanelloides — Ligularia, Rheum 

 nobile, some blue Gentians, and the bladder-headed Saussurea were the most 

 notable. The plants I found on the pass are those enumerated by Sir J. D. 

 Hooker. In addition to his list, I may state that Meconepsis horridula, a lovely 

 plant affecting only the most inclement situations, was collected in full bloom 

 from under the shelter of rocks. I stayed for two hours at the pass in the vain 

 hope of the fog lifting to give me a better view. During this time the con- 

 tinuous winds were most variable, and the variability was rendered more 

 obvious by the way in which vapour was deposited by different currents. The 

 wind which blew from the Tankra Valley on the south-west brought hail and 

 snow, that from the south-east in Tibet precipitated rain. The same meteoro- 

 logical conditions prevailed during Sir J. D. Hooker's visit. The Tankra La 

 lies south of the summit of Tankra Mountain, to the east is a long rocky 

 ridge cleft by the minor pass of Kanko La; and between this and the culminat- 

 ing peaks is a large, shallow basin with undulating surface through which flow 

 the headwaters of the Tankra River. Those on the north spring from many 

 points under snow fields, that on the south-east rises below the pass and is 

 immediately lost in the great central moraine, re-appearing at its lower end as 

 a large and swiftly-flowing torrent. It is joined near the Kanko La by the 

 united streams from Tankra ; after effecting the junction, the river turns 

 sharply to the west through the deep and narrow defile of the pass and hastens 

 precipitately downwards for some miles until it debouches in the Lachung 

 River, a little south of the village of that name. From the Kanko spur to the 

 limit of Pines at 13,000 feet, the valley is broad and shallow ; here it suddenly 

 narrows and remains so to its termination. During the week I spent on this 

 excursion, the weather was uniformly boisterous and wet, while those of my 

 party who remained below at Lachung asserted that they had enjoyed calm 

 sunny days and clear nights. 

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