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snow in Spitzbergen. These little plants first clothe the naked 

 rock ; some of them almost too small for vision unless accu- 

 mulated in myriads are yet the simple agents employed to 

 change the rocky mountain into the waving forest, or the sandy 

 desert into the fruitful province. So slow is the process at 

 first that many years must elapse before the newly-erected 

 edifice becomes even grey with age, or in other words puts on 

 the first clothing of vegetation. After this the progress of 

 vegetable life is more rapid. The Lichens in their decay leave 

 a little earth where a green Moss soon springs up ; this col- 

 lects more earth, and a Fern or a Grass or some other plant 

 succeeds, and thus a bed of flowers arises even upon the barren 

 cliff and the mouldering wall ; but not here only are the Lichens 

 found, the earth abounds with various species, and on the 

 trunks of trees they are still more numerous. Their structure 

 is very simple, some of them are like a bunch of hairs or a 

 knot of green tape ; others cup-shaped, or club-shaped ; but 

 the greater part a mere stain or color upon various objects, or 

 else spreading about like a growing leaf. The seeds are found 

 in little cups or knobs seated upon different parts of the leaf, 

 or as it is called, the thallus. 



The most common species are Lecidia murorum, a fine 

 orange patch on walls and tiling, bearing its fruit in very 

 numerous cups. Peltidia canina grows in dark green patches 

 upon the ground among grass, having its seeds in brown patches 

 around the edge of the thallus. Evernia prunastri which is 

 a small tuft of short, branched, light green, flattish threads, 

 seldom seen in fruit and growing upon palings and trees. 



The CUP LICHEN, almost everywhere, and at all seasons, 

 looking like an extinguisher stuck into the ground by its point ; 

 very often from the edge of the cup thus formed a second cup 

 grows, and this bears the fruit at the top of it, of a brown 

 color ; the thallus or other part of the plant is of a whitish - 

 green color. Cladonia rangiferina, a tufted, much-branched, 

 white Lichen, growing among short grass, and bearing seed in 

 black spots upon all the branches. It covers almost all our 

 heaths. This is the Reindeer Moss, which covers whole countries 

 in the North, and affords almost the only food of the Reindeer 

 of Lapland. 



