Butters: plant distribution in the Selkirk mountains 323 



Poa alpina L. 

 Rubus sp. 



Sambucus sp. 



Saxifraga bronchialis L. 

 SoHdago multiradiata Ait. var. 



scopulorum Gray. 

 Thuja plicata Don. 

 Tsuga mertensiana (Bong.) Carr. 

 Viola pallens (Banks.) Brainerd 



Occurrence on 



south moraine Notes 



A Very dwarf 



— Small bushes, not in flower 



or fruit 



— Small bushes, not in flower 



or fruit 



Seedlings 

 Small shrubs 



Summary of Tables I and II 



It will thus be seen, that of the 110 species found altogether 

 under the Sir Sandford moraines, only 34 (30.9 per cent) occur on 

 both moraines, while 76 (69.1 per cent) have been found on only one 

 moraine. Moreover, of the 34 which occur on both moraines, 13 

 (11.8 per cent) differ greatly in abundance in the two cases. This 

 leaves only 21 species (19.1 per cent) which occur with even 

 approximately similar frequency on the two moraines, i. e., which 

 have the same or consecutive index letters in the two cases. 



In a similar way, if we take into account only the 68 plants 

 which are listed as abundant (A or B) on at least one moraine, we 

 find that only 11 of these (16.2 per cent) are abundant on both, 17 

 (25 per cent) are abundant on one and scarce on the other, while 40 

 (58.8 per cent) though abundant on one moraine have not been 

 found at all on the other. 



This great difference in flora is emphasized by the fact that the 

 plants which are found only on the south moraine are nearly all 



