164 LAKE SUPERIOR. 



LAKE SUPERIOR. EUROPE. 



BETULA CE^E. 



Betula papyracea Ait. Betula pubescens Pall. High Jura. 



" excelsa Ait. " nana L. Peat bogs of the high 



Jura. 



" pumila L. 

 Alnus incana Willd. Alnus glutinosa L. Valleys of the 



Jura. 



" viridis DC. " viridis DC. The Handeck, in 



the Bernese Alps. 



Salix pedicellaris Pursh and others. For the willows and poplars, which 



are rather extensively distributed 

 aquatic plants, see the second list. 



About Lake Superior the Amentacese are represented only by species of 

 cold countries, or subalpine regions, and are, with a few exceptions, the same 

 as those of Europe. The Quercus rubra is scarcely an exception, since the 

 Quercus pedunculata ascends the valleys of the high Jura ; we find very large 

 trunks of it in the marshes of the Verrieres, on the frontier of France and 

 Switzerland. 



VLMACEJE. 



Ulmus fulva L. Ulmus effusa Willd. Banks of the 



" americana L. Doubs. 



URTICACEJE. 



Humulus Lupulus L. Humulus Lupulus L. Hedges of Val 



de Travers. 



Urtica canadensis L. Urtica dioica L. Everywhere. 



These two species spread diversely 

 in various regions, and have no- 

 thing characteristic. 



CONIFERS. 



Pinus Strobus. L. Pinus sylvestris L. Declivities of the 



Jura. 

 " resinosa L. " Pumilio Clus. Peat bogs of the 



higher Jura. 

 " Banksiana Lamb. " Cembra L. Declivities of the 



Alps. Handeck. Glacier of 



the Aar. 



