Insect Life on Western Arctic Coast of America 31k 
willow twigs or large plant seeds, and thus evade the notice of water birds. 
The pupa now develops in and partly fills the case, which shows three divisions: 
first, large, swollen, cylindrical front- end with a lid, by the aid of which the fly 
later emerged; second, a constricted "neck," and finally the "caudal" part, 
also cylindrical but smaller than the " cephalic " pai't, and containing air bj' 
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 U-shaped, 
the neck curving so that the part of the puparium containing the pupa also 
touches the water-surface, and the imago can emerge by the opening of the 
"lid." This process was observed with one of these pupae collected July 19, 
1915, and the imago emerged four days later/from a pupa collected July 3, 
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 out again 
but remains floating. 
On the margin of a large lake inland from Bernard harbour, a gi;eat number 
of freshly emerged midges of both sexes were in copula on the 15th. In the 
marginal water were many Chironomus (pupae and adults), besides perlid and 
trichopterous larvae. Branchinecta paludosa, amphipods {Gammarus lirnnaeus) , 
and other freshwater invertebrates were found in many of the nearby lakes. 
July 21-31, 1915 
Insect life is now very similar to that in the middle of July. Mosquitoes 
(Aedes sp.) are very numerous and annoying on warm, clear days, most of the 
larvae and pupae in the ponds having transformed (PI. I, fig. 2). Various flies 
and crane-flies {Lminophila sp., Stygeropis sp., Nephrotoma sp., Tipula sp., 
etc.), sawflies, and parasitic wasps are common, but neuropteroid imagines 
are comparatively few. Bumble bees (Bombus neohoreus, B. sylvicola, etc.), 
especial!}' the queens and workers, are busily visiting the many flowers now 
out. Tavo of the willow species (SaJix anglorum, S. pulchra) have now 
dropped most of their male catkins, but those of S. reticulata are in full bloom. 
Many butterflies (Erehia sp., Brenthis sp., Colias sp., Oeneis sp., etc.) and moths 
are seen on clear, calm days; of the former a female specimen of Pieris occident- 
alis was secured. The advent of this butterfly appears to 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 maggots were 
noticed in rotten seal-meat, ))ut could not be reared. 
August 1-10, 1916 
The following flying insects were noticed: 
Bumblebees {Bomhus sp.) 
Sawflies 
Wasps. para.«itic ( E:>-oh/iiis sp., Dioctes sp.) 
Butterflies {CoUas sp., Oeneis sp., BrentMs sp., Lycaena aquilo) 
Moths (Homoglaea, Titanio sp., Microlepidotera, etc.) 
Crane-flies {Erioptera sp., Tipula sp., etc.) 
Flies 
Mosquitoes (Aedes sp.) 
Neuropteroid imagines 
The Colias and Brenthis prefer low, grassy land or gravel supporting flowers; 
the moths are found on clayey or gravelly bluffs or slopes. The mosquitoes are 
less troublesome than in Jul3^ 
Sawfly larvae may be seen boring in the female catkins or making galls 
upon the leaves of willows. A larger sawfly larva fed on the leaves of bushy 
willow^ (Salix pulchra) from which, owing to its colour and quiescence, it is 
with difficulty distinguished. Efforts to rear it progressed no farther than the 
pupating stage, October, 1915. The common hemiptera {Chiloxaiithes stel- 
latus) and smaller bugs (Lobopidea sp., etc.) and the common collembola, 
mites, spiders, beetles, caterpillars, etc., are met with. 
