126 FIRST FORMS OF VEGETATION. 
as in the lichens which grow in shady forests, 
but which becomes oxidized, and changes to 
every shade of brown and black, when exposed 
to the powerful agencies of light and heat on 
the bleak barren rocks on the mountain side and 
summit. These gloomy lichens, associated as 
they almost always are with the dusky tufts of 
that singular genus of mosses the Andreas, give a 
very marked and peculiar character to many of 
the Highland mountains, especially to the summit 
of Ben Nevis, where they creep, in the utmost 
profusion, over the fragments of abraded rocks 
which strew the ground on every side, otherwise 
bare and leafless, as was the world on the first 
morning of creation, and ‘reminding one of the 
ruins of some stupendous castle, or the battle-field 
of the Titans. Some of the Alpine lichens, how- 
ever, are remarkable for the vividness and brilliancy 
of their colours. The mountain cup-moss, with its 
light-green stalk clothed and filligreed with scales, 
and emerald cup studded round with rich scarlet 
knobs, presents no unapt resemblance to a double 
red daisy. It grows in large clusters on the bare 
storm-scalped ridges, and forms a kind of minia- 
ture flower-garden in the Alpine wilderness. The 
loveliest, however, of all the mountain lichens is 
the Solorina crocea, which spreads over the loose 
mould in the clefts of rocks, and on the fragments 
