LICHENS. 145 
forms altogether the food of that animal during the 
prolonged northern winters. This lichen grows 
sparingly in little tufts among the heather in this 
country, and sometimes whitens the sides and 
plateaus of the Highland hills, covering bare and 
verdureless places where the snow first falls in 
winter, and lingers longest in summer ; but it is 
in the vast sandy plains called by the Laplanders 
Flechten-tundra and Moos-tundra, as lichens or 
Fic. 10.—CLADONIA RANGIFERINA. 
mosses predominate, which border the Arctic 
ocean, that it flourishes in the greatest profusion 
and luxuriance. There it completely covers the 
ground with its snowy tufts, and occupies as con- 
spicuous a place in the economy of nature as the 
grass in warmer regions. Linnzus says that no 
plant flourishes so luxuriantly as this in the pine- 
forests of Lapland, the surface of the soil being 
completely carpeted with it for many miles in 
K 
