150 THE FOREST LANDS OF NORTHERN RUSSIA. 



temperature during the summer months is much higher 

 at Enontekis than at the Cape ; and the power of vegeta- 

 tion is regulated more by the heat of summer than the 

 cold of winter. In those countries, also, where the ground 

 is long covered with snow, the temperature of the earth is 

 considerably higher than that of the air, and this preserves 

 it in a proper state for vegetation, in spite of the intense 

 winter cold of the atmosphere. Thus, at Enontekis the 

 ground is constantly covered with snow from the begin- 

 ning of October to the beginning of May ; while at the 

 Cape, in consequence of the vicinity of the sea, it is more 

 frequently exposed to thaws. Sometimes it happens in 

 the Lapland Alps, that, when a colder summer than usual 

 occurs, the snow lies during the whole year, and all kinds 

 of vegetables are completely destroyed, except a few 

 lichens, Polytricha, and Peltidea crocea. This is an event 

 which occurs more frequently in Norwegian Lapland, 

 where there are greater rains during summer, which 

 reduce the temperature of the air, and prevent the disso- 

 lution of the snow, or even convert it into ice. The pro- 

 gress of the seasons may be readily perceived from the 

 following table of observations made at Utsjocki, upon the 

 river Tana, in 69 53' North Latitude. 



Jan. 21. The sun's half -disc seen above the horizon. 



May 5. First rain fell. 



June 5. The ice disappeared upon the river Tana. 



June 28. The lakes were free from ice. 



July 15. Night frosts began. 



Oct. 18. The rivers froze. 



Oct. 25. The lakes froze. 



Nov. 3. The ground covered with snow. 



Nov. 20. The sun under the horizon. 



' During the winter solstice, when the sun continues 

 during seven weeks together under the horizon, instead of 

 a clear daylight, there is only a twilight of a few hours. 

 It is not so dark, however, but that a person might see to 

 write, or do any ordinary business from ten o'clock in the 

 forenoon to one o'clock in the afternoon; while the 

 superior brightness of the moon and stars at this season, 



