GEOGRAPHICAL DISTRIBUTION OF TREES. 49 



through which it passes, in proportion as it rises in alti- 

 tude, the degree of weakness of vegetative life. To the 

 weeping birch succeeds the betula acer, which replaces the 

 white birch ; after which comes the birch of the prairies, 

 which passes in its turn through different gradations of 

 size, and which at the Polar Circle is nothing more than a 

 stunted shrub, of pyramidal form, and covered with moss. 



In a paper on European forests, which appeared in the 

 Building Neivs for 1878, it is stated : ' The total area of 

 forest- producing land in Norway is computed at about 

 37,000,000 acres, but in this survey considerable so-called 

 forest land consists of comparatively unproductive rocks, 

 swamps, and moors. The pine and fir. even more than in 

 Sweden, constitute the riches of the Norwegian forests. 

 The Scotch fir is found up to the most northern latitudes, 

 and grows there up to a height of 3,400 feet above the 

 sea level. The spruce fir ceases near the Arctic Circle. 

 The forests are principally situated in the east of Norway, 

 near Christiania, Hamar, Trondhjem, and Christian sand. 

 Those of Bergen have long since been exhausted. In the 

 western districts of the country forests can hardly be said 

 to exist. As in Sweden, strict forest laws are now in 

 force, but the mischief done in former times by indiscri- 

 minate felling will take a long time to repair. 



