The Insects of the "Danmark" Expedition. 41^ 



however, it gave up doing this and hiy as if dead on the bottom of 

 the glass, and as it refused to take any food it only remained 

 alive two days longer". 



The above may be considered as typical of the hibernating 

 butterfly larvae, whether found in tufts of plants or under stones. 

 If one is fortunate, the black Hemipter Nysius may also be found 

 passing its winter sleep in the grass and such like, or a solitary 

 queen of Bombus hyperboreus, and by digging into the ground (a 

 difficult task at this time of year) the hibernating larvae of Tipiila 

 arctica and other Dipters. Otherwise most of the entomological 

 collections obtained on the ground at this time of year consist of 

 year-old, empty egg-capsules of spiders (under flat, loose stones) and 

 ruptured pupa cases of flies (especially amongst the moss) and 

 butterflies (below stones, in tufts of plants). 



If we come now to a freshw^ater lake, we find, if it is not frozen 

 to the bottom, a much richer animal life. Looking down through 

 the ice we can see masses of the quite small, reddish brown Cyclops 

 hopping about in the water right down to the bottom; the dark- 

 brown Daphniae are constantly moving about with great leaps or 

 springs, or some of them are dead but have left behind their edged 

 and flat winter-eggs to sink down to the bottom of the lake; Apus 

 glacialis in different sizes swims up under the ice, crawls over the 

 plants or hastily buries itself down in the mud. Taking some of 

 the latter up we find living in it numerous, red larvae of gnats 

 {Chironomiis); other gnats also hibernate as larvae. As all the lakes 

 there, which are shallower than 1 — 2 meters, freeze to the bottom 

 in winter, all these (mainly littoral) animal forms must be able to 

 stand being frozen in the mud for a long time. If the frost surprises 

 Ihem up in the water, however, they undoubtedly die — a fact of 

 which I have seen many examples in North-East Greenland (where 

 the ice is often found full of dead Apus glacialis). 



For the sake of completeness it may be added, that the parasitic 

 insects there (the louse Haematopinus trichechi on Trichechus rosmarus, 

 Pulex glacialis on Lepus uariahilis and the various Mallophagae on 

 Corvus corax, Lagopus mutus etc.) are just as common in winter as 

 in summer. 



There is no true spring in North-East Greenland. Gradually 

 as the sun remains longer and longer above the horizon and its 

 warming capacity increases from day to day, the snow slowly melts 

 and evaporates; larger and smaller spots of ground become free of 

 snow; a bole is first formed in the snow where a tuft of grass or 



