Insect Life on Western Arctic Coast of America -Uk 



willow twigs or Large planl seeds, and thus evade the notice of water birds. 

 The pupa now develops in and partly fills the case, which Bhows three divisioi 



first, large, swollen, cylindrical front-end with a lid, by the aid of which the fly 

 later emerged; second, :i constricted "neck,'' and finally the "caudal" pai 

 also cylindrical but smaller than the "cephalic " part, and containing air by 

 which the puparium rises to the surface and floats with the air chamber upper- 

 most. Just before the emerging of the imago the puparium becomes l -sh iped, 

 the neck curving so that the part of the puparium containing the pup:, also 

 touches the water-surface, and the imago can emerge by the opening of the 

 "lid." This process was observed with one of these pupa' collected July IP. 



1915, and the imago emerged four days later; from a pupa collected Jul;. 



1916, the imago emerged the following day (Rearing 78). The fly itself is also 

 aquatic. As soon as the imago has emerged the puparium stretches nut again 

 but remains floating. 



On the margin of a large lake inland from Bernard harbour, a great numl 

 of freshly emerged midges of both sexes were in copula on the loth. In the 

 marginal water were many Chironomus (pupae and adults), besides perlid and 

 trichopterous larvae. Branchinecta paludosa, amphipods (Gammarus limncu 

 and other freshwater invertebrates were found in many of the nearby laki 



July 21-81, 1915 



Insect life is now very similar to that in the middle of July. Mosquil 

 (Aedes sp.) are very numerous and annoying on warm, clear days, mosl of the 

 larvae and pupae in the ponds having transformed (PI. I, fig. 2). Various flies 

 and crane-flies (Limnophila sp., Stygeropis sp., A'</>lirot<>rna sp.. Tipula -p.. 

 etc.), sawflies, and parasitic wasps are common, but neuropteroid imagines 

 are comparatively few. Bumble bees (Bombus neoborexts, B. sylvicola, etc 

 especially the queens and workers, are busily visiting the many flowers now 

 out. Two of the willow species (Salix anglorum, S. pub-lira) have now- 

 dropped most of their male catkins, but those of S. reticulata are in full I. loom. 

 Many butterflies (Erebia sp., Brenthis sp., Colzas sp., Oeneis sp., etc. I and moths 

 are seen on clear, calm days; of the former a female specimen of !','< ris occidt nt- 

 alis was secured. The advent of this butterfly appears t<> synchronize with 

 the first blooming of the cruciferae (Sisymbrium sp., etc..) on which, probably, 

 the larvae feed and which the imago seems to prefer. Muscid n wen 



noticed in rotten seal-meat, hut could not be reared. 



August 1-10, 1915 



The following flying insects were noticed: 

 Bumblebees (Bombus sp.) 

 Sawflies 



Waspe, parasitic (Exolytus sp., D ip.) 



Butterflies (Colias sp., Oeneis sp., Brenthis sp., Lycaena aqiMo) 

 Motbs (Homoglaea, Titanio sp., Microlepidotera, c 

 Crane-flies (Erioptera sp., Tipula sp., etc.) 

 Flies 



Mosquitoes (Aedes sp.) 

 Neuropteroid imagines 



The Colias and Brenthis prefer low. grassy laud or gravel supporting Bowel - 

 the moths are found on clayey or gravelly Muffs or slopes. The mosquitoes are 

 less troublesome than in July. 



Sawfly larvae may be seen boring in the female catkin- or making galls 

 upon the leaves of willows. A larger sawfly larva U'd on the leaves of bushy 

 willow (Salix pulchra) from which, owing to it- colour and quiescence, it is 

 with difficulty distinguished. Efforts to rear it progressed no farther than the 

 pupating stage, October, 1915. The common hemiptera (Chiloxanthes st,l- 

 latus) and smaller bugs (Lobopidea sp.. etc.) and the common collembola 

 mites, spiders, beetles, caterpillars, etc.. are met with. 



