458 I. P. Косн. 
Besides the meteorological temperature the solar radiation plays 
an extremely great part in the life of plants. Among others LUNDAGER 
has demonstrated this on the Danmark-Ekspedition by undertaking 
a series of temperature measurements with a black bulb thermo- 
meter"). As soon as the snow has disappeared, the soil is strongly 
heated by the solar radiation, and in this manner heat is again 
conveyed to the lower strata of the air. As we have seen, it is how- 
ever in the very months of May and June that the fog settles over 
the outer coast and prevents the continued solar radiation. The 
importance of this appears among other things from the fact that 
the rivers at the eastern part of Ymers Nunatak — about 55 km to- 
wards the interior of the inland ice and at an altitude of about 
800 m above the level of the sea, the mean temperature of which 
locality may be estimated at about + 20° — in 1908 broke up in 
the middle of May, whereas at Danmarks Havn they only did so a 
month later. It may therefore justifiably be presumed that the 
spring and summer manifest themselves at an earlier period, as well 
as more strongly, at the margin of the inland ice than at the outer 
coast. 
The fog conveys moisture to the soil or at least checks the 
evaporation, and the summer must consequently become drier, the 
less fog there is. In 1912 it also seemed to me that the mountainous 
tracts in the land south of Hellefjord (Daniel Bruuns Land) has a 
still sparser vegetation than the mountain stretches near the outer 
coast. But the increasing dryness of the climate plays no part, as 
far as the bogs are concerned, seeing that the drifts of snow can” 
supply sufficient water for the irrigation of the latter. On the west 
side of Daniel Bruuns Land, in other words right up to the inland 
ice, there are many and comparatively large boggy tracts, the largest 
of which is, roughly speaking, about 30 square kilometres. 
To the Danmark-Ekspedition the existence of this comparatively 
luxurious boggy vegetation in Daniel Bruuns Land was unknown. 
Nor did we consequently know at the time that in this very place 
there were larger quantities of musk oxen and hares, and perhaps 
also of foxes, than in any other part of Germania Land. 
In this connection I shall mention an observation, which possibly 
has to do with the peculiarity that the sea fog only in exceptional 
cases reaches higher than 300 m, that is, the presence (end of July 
1912) of large swarms of mosquitoes in the Moskusoksefjeldene, which 
made a night we were compelled to spend in one of the mountain 
1) AnDR. LUNDAGER: Some notes concerning the vegetation of Germania Land, Medd. 
om Grønl. XLIII, pp. 372—381. 
