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The Tree Flora of the Prairies is extremely meagre. 

 Chiefly small poplar by the river hanks, and round the pools. 



Certain tracts of the Prairie, where the underlying 

 Cretaceous rock has been denuded of the alluvium and 

 eroded, or where we have small isolated drainage areas 

 without any outlet except evaporation, a saline condition is 

 found greatly modifying the Flora. The genera are. mostly 

 the same, but the species are distinct, and all assume a grey 

 green, mealy or hoary appearance, which distinctly marks 

 the landscape. This is the so-called " Sage Scrub." The 

 most striking plants here are the aromatic Artemisias, and 

 two dwarf Cacti, Opuntia Missouriensis, and Mamillaria 

 vivipara. 



Passing from the Prairie with its entirely American Flora, 

 to the Rocky Mountains, a remarkable change is at once 

 observed. As the Flora becomes alpine, the genera and 

 species approximate more and more closely to our own Swiss 

 and Scotch alpine Flora ; this alpine Flora is therefore of 

 great antiquity, and has survived the climatical changes of 

 long ages — changes the operation of which have been common 

 to the whole Northern Continental area of the world. In 

 one long day's ramble among the mountains from the 

 summit of the Kicking Horse Pass up to the snow line, 196 

 species of plants were gathered and named, of these about 

 40 per cent, were European. Among them were many of 

 our most familiar and beautiful Alpines, such as Silene acaulis, 

 Saxifraga oppositifolia. Lychnis alpina, Dryas octopetala, 

 Draba incana, Oxytropis campestris, Potentilla fruticosa, 

 (a Tcesdale plant, there growing on or near Basaltic intrusive 

 dykes, as it does also on the shores of Lake Superior) 

 a Trollius closely allied to ours, Carex atrata, &c., &c. 

 The ferns also are identical with our own ; the Holly 

 Fern, Parsley Fern, Asplenium Trichomanes and viride, 

 Cystopteris montana, Woodsia, Lycopodium annotinum, &c. 

 The most marked absentees, are the Primulas and 

 Gentians, which form so striking and beautiful an element of 

 the European Alpine Flora. 



