CAPT. MAUKIIAM AT FORT CHURCHILL, ETC, 
3G5 
of light ; ill short it does uot appear that, given the necessary 
conditions of equable climate, ther^ would be any insurmountable 
obstacle to luxuriant vegetation in the present proportions of day 
and night in lat. 82 "27, as the blaze of light during the time when 
the sun remains above the horizon without setting, might neutralise 
the effect of the darkness of the winter, and the average amount of 
light received by the plant during the whole year might bo as 
great as that received in constant shade. At first sight the greatest 
difliciilty appears to present itself in the case of evergreens such 
as Magnolia ; but evergreens are by no means absent from the 
Arctic flora oven under present conditions. There are at least six 
evergreen plants which still grow in high latitudes in the Western 
1 lemisphero : — 
PvROLA ROTUNDiFOLiA cxtonds to GOT 5 M. 
lillODODENDRON LAPPONICUM „ 72-20 
PlIYLLODOCE TAXIPOLIA „ 72-20 
LoISELEURIA PROCU>ri3EN3 „ 72 '20 
Empetrum nigrum „ 78-45 
Cassiope tetragona „ 78-50 
ami this last in the Eastern Hemisphere, at Spitsbergen, very 
nearly touches the eightieth degree, being found at 79-20 X. 
It seems safer to assume the adaptation of plants to their 
circumstances, than to reipiire the alteration of circumstances at a 
great and unknown distance of time in order to account for the 
presence in high latitudes of the representatives of jilants which 
are now living under w-hat wo consider a more favourable 
distribution of light throughout the year. The adaptability of 
plants to their circumstances is very great; for instance, Silene 
acaulis, which descends to the sea level in Shetland, was found by 
Meyer at 10,370 feet above the sea in the Bernese Oberland, and 
by Saussuro at 11,392 feet on Mont Blanc, flourishing and 
flowering at a height of from 1,500 to 2,500 feet above the level 
of perpetual snow. 
Supposing the three floras or equal latitude to which we have 
alluded, that of Digges Island, the Fieroes, and the Sogne Fiord, 
to be preserved in a fossil state and examined by geologists of 
a future time, when by some alteration of the level of the land 
the present set of the oceanic currents was altered and a warm 
