SOUECES OF PIOTUEESQUENJjJSS IN TREES. 27 



prevails in any degree, is a clear indication tliat 

 the vigour of tlie tree is declining. We find, also, 

 anotlier species of moss, of a dark brown colour, 

 inclining nearlyto black; another of an ashy colour, 

 and another of a dingy yellow. We may observe, 

 also, touches of red, and sometimes, but rarely, a 

 bright yellow, which is like a gleam of sunshine ; 

 and in many trees you will see one species growing 

 upon another — the knotted, brimstone-coloured 

 fringe clinging to a lighter species, or the black 

 softening into red. Strictly speaking, many of 

 these excrescences, which I have mentioned under 

 the general name of mosses, should be distin- 

 guished by other names. All those, particularly, 

 which cling close to the bark of trees, and have a 

 leprous, scabby appearance, are classed, I believe, 

 by botanists, under the name of lichens : others are 

 called liver-worts. But all these excrescences, 

 under whatever names distinguished, add a great 

 richness to trees; and when they are blended 

 harmoniously, as is generally the case, the rough 

 and furrowed trunk of an old Oak, adorned with 

 these pleasing appendages, is an object which will 

 long detain the picturesque eye. 



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