10K 



Canadian Arctic Expedition, 1918-18 



The three periods of each month under which insect life is described in the 

 following pages must not be taken too literally; future investigations may 

 extend considerably the period in which certain species are out, and also add 

 species not yet found. Nor can observations on reared insects be considered 

 to hold good for insects living under normal conditions. In the main, however, 

 the data given are correct, especially for the more common forms. 



Beginning of May, 1-10 



Early in May (1914) the weather was warm, the snow started to melt, and 

 the shallow tundra ponds became free of ice. In these ponds various big 

 dipterous larvae, especially tipulids (Stygeropis sp., etc.), were found lying dead 

 on the bottom or already actively boring in the soft mud. Dytiscid beetles, 

 midge larva;, etc., are probably also present, but were not noticed until later in 

 the month. 



The other hibernating insects, carabid beetles (Pterosticus mandibularis. P. 

 agonus, Nebria sp.), lepidopterous larvae, collembola, flies, spiders, and mites are 

 still found in plant tufts, under stones, and driftwood, etc., as during September 

 and the winter, keeping immobile until exposed directly to the sun. 



Middle of May, 11-21 



Even now the hibernating insects are found immobile in their hiding places. 

 The following typical instances are taken from the writer's field-journal: 



"May 12, 1914. Demarcation point, Alaska. "Found a full-grown 

 Agrotid (?)-larva 3J cm. long stuck into a Dryas plant on the coastal 

 tundra. The larva lay curled up between the leaves and twigs about 

 i-inch below the surface and hidden by dead leaves. Below the larva 

 the ground was completely frozen. When removed the larva moved very 

 slowly; and when laid in a box only used its abdominal feet to take a 

 grip. Later, when brought into the house, the larva livened up com- 

 pletely and began to crawl around. Efforts to rear it were unsuccess- 

 ful. The day was calm and sunny; temperature from 9 degrees to 30 

 degrees F. and higher on direct exposures." 



The first flies ot the year, three kinds, probably hibernating forms, were seen 

 May 13, 1914, at Demarcation point (PI. Ill, fig. 2). The weather was still 

 clear, but warmer (35 degrees F.) One species of the flies, Phormia terranovae, 



