The Insects of the "Danmark" Expedition. 43 



But it depends naturally on both the situation and physical condi- 

 tions of the different places, when ргесдзе!}»^ the insects come out 

 at the one or the other spot (on the plant-covered rocks at the outer 

 coast and on sheltered grounds earlier than at other places), — just 

 as the appearance of summer is not always at the same time two 

 years running (thus in 1908 it was much later than in 1907). 



But as soon as we come into June and have a positive mean 

 temperature, ra})id advance is made by all things. The migratory 

 birds have now arrived from the south and seek their food in the 

 many pools of melting water, Avhich are now formed, or at the 

 margin of the lakes. The flies ^ are troublesome and collect in great 

 crowds on the refuse lying about the tent, and the first gnats 

 {Culex nigripes) make their presence felt in an emphatic manner. 

 Every lake and pool is filled with the larvae of gnats and on 

 the bottom lie dead earth-worms and larvae of flies, which 

 the water has washed up from the bottom-soil. The ground thaws 

 some inches down and the greater part of the low-lying land is 

 converted to bog. The лvater from the melting snow, which is daily 

 increased from the larger and smaller stretches of snow still lying, 

 streams down over the flat, evenly sloping plains, or it follows its 

 own-made small courses down towards the sea-ice. There is practi- 

 cally not a single one of the places bare of snow which is free of 

 water, and the caterpillars appearing are badly off. Occasionally 

 Ave find them drowned in the water, but they nevertheless often 

 manage to save themselves by moving on to the higher lying tufts 

 of grass, stones and the like, to wait there for better times. 



Every day that now passes makes the summer more and more 

 evident. Green shoots appear everywhere on the plants and the first 

 flowers {Saxifraga oppositifolia, Salix polaris) have come out. Most 

 of the low-lying country apart from the permanent stretches of bog 

 and the water-courses becomes bare of snow and running water, even 

 though the snow higher up only melts towards the end of the month 

 when the large rivers also become free. The caterpillars are now 

 out generally in all sizes (especially Dasychira); they collect the 

 utmost possible of food befoi-e pupation lakes place. Other insects 

 now out, in addition to the flies, are small forms of gnat [Chiro- 

 nomiis) and butterfly (Penthina), common as imagines. Occasionally 

 we find Dasychira larvae which seem strangely dead, seated for 

 example on a Saxifraga tuft; taking one up we find that it is fixed 

 fast to the plant, and on tearing it loose we see that only the empty, 

 hard skin of the larva remains, whilst a large cocoon of an ichneu- 



' Probal)lv hibernatinsi as imagines. 



