18S4.] FOBEST BOTANY IN XOEWAY. 423 



The Birch often takes an elegant form with the exterior branches 

 pendant in long clusters measuring as much as 5 metres, 17 feet. 



The Birch may attain to a great age. This tree, and especially the 

 form with long pendant branches, is the ornament of the valleys of 

 JSTorway ; certain specimens in isolated groups having acquired by 

 their beauty a widespread fame, and are protected not only by the 

 proprietors, but by the whole population of the valley, who are proud 

 of them. They have generally particular surnames, borrowed ordi- 

 narily from the property to which they belong ; one famous specimen 

 is the Holsbirh, so called from the name of the estate. Hoi, Eennebu, 

 in Orkedal, in the prefect of Soddre-Drontheim, 62° 58' IsT. 



The Willow of Norway, Salix caprea, known in Britain as the 

 Great Eound-leaved Willow, is very much diffused over the forest 

 regions of Norway, and even beyond the elevation above the level of 

 the sea attained by the Fir and the Pine ; and, as intimated, it may 

 be seen to flourish in higher latitudes, or at least as far north as either 

 of these trees. It grows at Hammerfest, 70° 37' N., but only as a shrub 

 or brush, and the allied tree, the Aspen, Populus tremula^ is 

 likewise spread over the whole of Norway. In the south part of the 

 country it may be met with, but in dwarfed condition, at an altitude 

 of 900 metres above the level of the sea. In the lower-lying country 

 it attains a height of 30 metres, and even at Alten, 70° N., in Finmark, 

 it may attain to 18 metres, 60 feet. Of Osiers, there are in Norway 

 about 20 wild species, the greater part of them taking the form of 

 bushes. They grow to a great elevation on the mountains, principally 

 on moist slopes. In southern Norway, on spots a little sheltered, they 

 may be found 1,500 metres above the sea level. 



To the same zone may be traced the growth of the Alder, Alnus 

 incana, D. C, known in England as the Hoary-beard Alder. It is 

 met with very frequently so far north as West Finmark, where it 

 may be seen with a height of 20 metres, 66 feet 8 inches, and a 

 diameter of 30 centimetres at the level of the ground ; and it grows 

 to almost the same altitude as the Beech, 



The Alnus glutinosa, Gent., the common Alder of Britain, is much 

 less frequently met with. It flourishes always in low valleys along 

 the banks of streams and in humid soil. It is scarcely to be met 

 with above an altitude of from 250 to 300 metres, and its Polar 

 limit is 64° N. lat. 



Of the Oak, two species are found growing wild in Norway, the 

 sessile Fruited Oak, Quercus robiir, W., and the Common Oak, 

 Q. pedimculata, W. The latter is found on the west coast up to 

 63° N. ; but the planted Oak up to 66° N. In the southern 

 parts of the country it scarcely ever extends beyond 300 metres 

 above the level of the sea. There are small forests of the Common 



