ne 
"4200 ON THE DISTRIBUTION OF PLANTS. 
localities. This point of view is of great importance in botanical 
geography, and has much to do with the question about the 
migration of plants. 
In the soil of our woods we commonly find beds of charcoal—so 
commonly, indeed, that we are brought to believe that all our woods 
have been burned once or more in the course of time. As dr 
be the common one he ne rh and especially 
plants with winged and hairy seeds and fruits easily transported by 
wind, or those with fleshy fruits devou or other 
animal, pecies are the birch, the aspen, the mountain ash, 
Eptlobium angustifolium, &. The last one is called by Norwegian 
peasants, ‘ means ‘‘the token of fire,” and has in 
Canada, for the same reason, the name of ‘‘ fireweed.” The pines 
do not last long, € heavier seeds of the conifers immigrate step 
by s € young pines and firs destroy, by overshadowing, 
the more light-lovi trees, and at length regain their old ground, 
s 
i r 
invaded only by the commonest species from the neighbourhood. 
in Norw: 
essentially the same. The rocks and slate and limestone cliffs, poor 
In vegetable soil, are permanent localities, too. Lakes too deep to 
be changed into peat mosses are in the same case. The sea-shore 
with the shore-line. Ip this manner even arctic plants may be 
found on our present shor 88, which were in arctic times submerged. 
