INTRODUCTION 
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the cover of the snow. In the last week in May the 
snow was gone, the country was green, the cuckoo was 
in the woods, the swallow about the houses, and the 
salmon springing in the fiords. Summer was come.” 
Snow is, both by its soft texture and want of colour, 
Viseful to the plants and seeds lying beneath it, being thus 
a bad conductor of heat. Plants under its protecting 
shelter never experience a greater degree of cold than 
32 degrees of Fahrenheit. 
Winter is the season allotted to that repose from 
growth which is necessary to the vegetable constitution; 
but the repose is not of that absolute nature which it 
is sometimes thought to be. The sap does not, as was 
formerly supposed, cease to flow ; but the fluids of plants, 
although in a languid state, continue to make some move- 
ment. It is owing to the comparatively torpid state of 
plants at this season that transplantation, if attempted, 
generally proves fatal. 
The mosses so num_erous and beautiful during winter, 
upon the old roots and stems of trees, are also provi- 
sions against the excess of cold ; and while they serve as 
a clothing to the trees, they add greatly by their ver- 
dure, and minute beauty, to the scene, in which bright 
tints have become unfrequent; their most common places 
of growth are cold situations and barren soils. 
In the summer this verdant covering preserves the 
trees from the heat of the sun, and by its power of readily 
imbibing, and long retaining, in its small cells, the moist- 
ure of the atmosphere, it secures the larger plant from 
the drought to which it might else be subjected. 
Those countries only which are situated within the 
Polar regions, and constantly covered with snow, are 
entirely destitute of plants, if we except the summits of 
those lofty mountains of other countries whence the ice 
never dissolves. The plants peculiar to very cold and 
elevated districts are chiefly diminutive in size, and bear 
blossoms which are large in proportion to the leaves. 
In such situations mosses and lichens are numerous ; and 
plants, having compound flowers, like the daisy, or cross- 
shaped blossoms, like the wallflower, are common, while 
some of the umbelliferous tribes, like the carrot and 
parsley are found there. 
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