if they germinated properly. When one considers the 

 fact that elevated forests are usually coni fer.ms, Myake's 



winter become of interest. One may well inquire if 

 trees of this kind obtain in this way a distinct advantage 

 over others at high altitudes. 



Turning to the low growing plants, we find their prob- 

 lems of a somewhat different nature. In the Alps, the 

 Caucasus, the northern Rockies and the Selkirks to men- 

 tion only a few examples, large tracts of lofty grassland 

 lie buried under snow until the close of the vernal period. 

 If one visits the higher forests of the Selkirks in June, 

 he must journey in the snow. Arriving at the alpine 

 fields, he finds them at the summer solstice, still hidden 

 under an almost unbroken covering of white. In the 

 month that follows, they will be gradually exposed. Dur- 

 ing the ten or fifteen weeks that remain, they must ac- 

 complish nearly the whole sum of their animal activities. 

 The ability to do this must be a decisive factor in their 

 struggle for existence. Carex nigricans ordinarily occurs 

 mingled with other plants; but in moist hollows, where 

 the snow has lingered until the middle of July, it often 

 forms patches to the entire exclusion of competitors. 

 Where the snow does not melt till the first of August, it 

 is absent and the visible vegetation consists of poly- 



trichum only. Where snow persists till late in August, 

 the soil thus exposed is destitute of visible vegetation. 



in this that of phanerogamous plants present the sedge 

 is best able to compress its life processes into a brief 

 period; that the moss is able to live with even shorter 



tain itself under conditions of such brevity of season as 

 are represented by twenty or thirty days at the close of 

 summer? It is hardly to be doubted that many other 



