8 



smooth, but generally rifted and broken, so as to present numerous 

 ledges with slopes of detritus at their base, patches of snow lying 

 in their crevices, and rapid streams rushing headlong down their 

 ravines. Fed by these and the melting snows, a deep mountain 

 tarn, or small lake, is seen in the lowest part of the corrie, of 

 which there are several on this mountain, whose waters seem either 

 black as ink in spots averted from the sun, or of the deepest blue, 

 sometimes green on their gravelly margins, where exposed to its 

 rage. Both rocks and lochs bear evident traces of glacial action 

 at different epochs, seen in the former in their grooved, scratched, 

 striated, and polished surfaces, and in the latter, more especially 

 the larger ones, in the manner in which they have, to some ex- 

 tent at least, been scooped out in their rocky beds — phenomena, 

 however, which are still more apparent on some of the other moun- 

 tains of this district. The vegetation of this zone throughout is 

 in every respect much more varied than that of the higher one. 

 In addition to the general covering which, except on the naked 

 precipices, it almost everywhere presents, of such very social plants 

 as grasses, carices, and short ling, as also numerous mosses and 

 lichens, the sides of the streams, the margins of the tarns, and 

 more especially the ledges of the precipices, are characterised by 

 the presence of those alpine plants, amounting throughout Great 

 Britain, in all the classes, to probably some 400 species, which 

 gladden alike the eye and heart of the phamogamic and crypto- 

 gamic botanist in their mountain rambles. On leaving these 

 corries, with their grand and desolate scenery, we begin to 

 enter the sub-alpine zone. This generally commences with 

 a somewhat flattish table-land of but limited breadth, 

 from which we descend into narrow lateral glens which 

 after a time open out into the main valleys, which, confined and 

 steep at first, gradually become wider and less elevated, till at 

 length the Alpine merges into the Lowland region. Over the 

 whole of this tract, which presents, here and there, expanses of 



