LIST OF TKEES AND SHRUBS. 313 



The following are specially arctic in their habitats: S. myr- 

 sinites, S. vestita, S. sjjeciosa, S. reticulata, and S. nivalis, which 

 grow on the peaks of the Rocky Mountains between 52° and 57° 

 north, and within the arctic circle, some of them reaching very 

 high latitudes. S. reticulata grows on the coast between York 

 Factory and Churchill. S. speciosa inhabits the Arctic Sea 

 coasts from Coronation Gulf to Kotzebue Sound, and ranges 

 southwards on the Mackenzie to about the 60th or 61st parallel. 

 It is perhaps the handsomest of the genus, having an agreeable 

 growth, and very large leaves, which are of a silvery whiteness 

 beneath, and when bruised have a rather pleasant odour. On 

 the Mackenzie it grows to the height of 15 feet, in form 

 of a bush, with very stout and long yearly shoots, which dis- 

 tinguish it from all the other willows of the same localities 

 On the coasts of the Arctic Sea, wherever the rivers afford a 

 suitable point of alluvial soil, a thicket of this willow may be 

 expected as tall as a man. Mr. Seeman observed it in the 

 tree form on the north-west coast, where it is from 18 to 20 

 feet in height, and having a stem five inches in diameter. It 

 resembles S. lapponum in its habit. S. stuartiana and S. re- 

 tnsa grow on the more northern banks of the Mackenzie and in 

 Kotzebue Sound, and have not as yet been detected south of the 

 arctic circle. S. rostrata, S. speciosa, S. lucida, S. longifolia, 

 S. depressa, S. reticulata, S. arctica, and S. polaris, have been 

 enumerated by authors as crossing to the Pacific side of the 

 Rocky Mountains in their respective zones. Salix glauca was 

 found by Seeman on the shores of Beering's Sea. 



The following are not confined to the American continent, 

 but range to either Europe or Asia, as well as to Rupert's Land, 

 or the arctic coasts : S. petiolaris, S. rosmarinifolia, S. vimi- 

 nalis, S. purpurea, S.fragilis, S. acutifolia, S.fusca, S. myr- 

 sinites, S. stuartiana, S. reticulata, S. herbacea, S. polaris 

 and S. ammaniana. 



The most common in Rupert's Land are the S. rostrata, which 

 extends southwards to New England, and in the north forms 

 almost impenetrable thickets 20 feet or mere in height, in which 

 the old twisted and sordid grey stems spread in all directions. 

 S. longifolia, which has the growth of an osier, covers the new- 



