The Insects of the "Danmark"' Expedition. 47 



found chiefly on mossy stretches and both the males and females 

 are seen, thongh the former are the most numerous and swarm in 

 the air in small groups, whilst the females sit singly on the ground. 

 Other imagines are met with flying about over the surface of the 

 water, often drowned in this and the ruptured pupa-cases float about 

 on the surface in thick masses. The biting insects are however not 

 yet troublesome with their numbers. 



The last insect order remaining to be mentioned is that of the 

 butterflies. One butterfly larva (for description see p. (55) forms 

 a roundish, compressed cocoon on the under side of flat, loose stones, 

 the one half being pressed into depressions in the stone, whilst the 

 other half is attached to the pieces of gravel lying below. Here it 

 pupates in the middle of June (unless attacked by a parasitic wasp), 

 and as the larva is only found on dry places bare of snow and poor 

 in vegetation, the pupa is insured agains the loosely woven and thin 

 cocoon being washed away by the water from the melting snow. 

 The Dasychira larvae pupate about the same time. In size and form 

 their cocoon resembles a pigeon's egg and is very dense; the outer 

 surface is smooth and light-brown to yellowish white whilst short 

 threads pass out from the under side in all directions; these serve 

 to attach the cocoon to the grass stalks under and around in such 

 a way that the cocoon hangs a little above the ground. We find 

 these cocoons mainly on mossy ground and even if there is water 

 underneath between the blades of grass, it does not damage the 

 cocoon. I have also found cocoons, however, which were firmly 

 attached directly to the upper side of stones. The inner layers of 

 the cocoon have a looser and more flax-like texture than the outer, 

 smooth layers, and the cocoon is also less dense at the broad end 

 within which lies the head end of the pupa. The pupation of the 

 larvae of Anarta and Cidaria proceeds in a considerably easier 

 manner; they simply throw oft" the shell of the larva, which in the 

 Dasychira pupa lies inside the cocoon, and the smooth, brown 

 pupa fixes itself in between the dense leaves on the under side of 

 the Dryas or other plants. With regard to the imagines, the first 

 of these met with are small forms (Penthina and others), then follow 

 Argynuis (ca. 25th June) and Anarta (probably also Dasychira) at the 

 end of the month, whilst Colias hecla and Lycaena a<iuilo var. orbi- 

 tuhis are first met with in the beginning of July. 



That the spiders, mites and spring-tails (the last under flat 

 stones) are now common need perhaps only be mentioned; the 

 palps of the male of the first are very much swollen, a sign that 

 the pairing time is at hand. This applies also to Tipula arctica, 

 often taken in copulation. 



