Insect Life on the Western Arctic ( 'oast of Arm rica 13k. 



On the tundra plants are various hemiptera {Euscelia hyperboreus, Calo- 



canthia trybomi, etc.) and spiders (Xysticus bimaculatus, Lycosa sp. : the / 

 makes a funnel-shaped web in fissures of the ground, in which it takes refuge, often 

 first dropping its prey consisting of tipulids, flies, beetles, or other Bpiders; the 

 Xysticus are found among leaves. Now and then a decomposed dead animal 

 harbouring muscid-eggs or larvae attracts the beetle Silpha lapponica. On 

 driftwood sticks or dead leaves are cakes of red mite eggs (Bryobia prcu 

 from which the equally red larvae will emerge in a few days. Conspicuous a 

 are the larvae and cocoons of Gijnaephora rossi. The first moths of this Bpe< 

 now emerge, unless parasitized by the tachinid fly {Eurphorocera gelida) or by 

 an ichneumonid wasp (Amblyfeles sp.). Of the former (fly) as many as Bix pupa 

 cases may be found together with the larval skin of the lepidopterous hi 

 some of the cases contain the dead fly-pupa (pale, with grey hairs and legs, eyes 

 red-brown) and attached to it six or more parasitic chalcid larva 1 , which later 

 emerge in August through small holes in the pupa case of the fly. Or the 

 Gynaephora cocoon may contain the dead lepidopterous larva or pupa, which 

 on opening will be found to contain a fat, white ichneumonid larva filling out 

 most of the host, the internal parts of which it has devoured, while the skin <>f 

 the caterpillar host protects it from drying up. Sometimes the parasite kills the 

 Gynaephora larva before the latter succeeds in making its cocoon and pupating; 

 it is then found that the ichneumonid pupa (another species?) has spun itself 

 to the ground, the caterpillar skin above protecting it from discovery by birds 

 and other enemies. 



By digging, or in plants, various larvae or pupae of insects (weevils, tipulids, 

 etc.) may be observed. 



The freshwater ponds and lakes now contain a rich life. Craneflies, emerging 

 from their pupa cases, float on the surface, or fly over the water, when not 

 resting on grass leaves, etc. Swarms of small flies swarm or spring on the water 

 surface; often they are seen in copulation. The first perlid adults crawl up 

 on grass leaves above the water and leave behind the nymphal skins on the 

 surface. Swimming in the water are thousands of mosquito larvae now grown 

 considerably {Aedes sp. etc.), copepods and the nauplii of the common phyllo- 

 pod (Branchinecta paludosa), besides mites (Curvipes reighardi), etc. < rawling 

 or resting on submerged logs, etc., are the large red Chironomus larvae in their 

 mud tubes. They are now pupating, the pupa emerging from its tube to the 

 surface where it floats on one side, until it has shed its larva skin and ran assume 

 a vertical position. 



July 1-10 



The following insects are now seen : — 



Flies Rhamphomyia erinacioides 



Si/rphius sodalis 



Aricia boreali-s 



1'horbia brevitarsis 



Piophila borcalis 



Botanobia frii 



Tipula subarctica ~\ Craneflies with 



Tipula arctica I nymphs of n 



Stygcropis parrii f (Hydrachnlds?) 



J'richyphona brci-if areata J on some of them. 



Sawflies ( Amauronematus sp.) 



li-hneumon fly (on willow plants) 

 Midges Tanypus ala-scensis 



Chironomus sp. 



Mosquitoes Aedes nearcticua 



Bumblebees Hombtts sp. 



Butterflies Brenthis frigga alaskensis 



B. frigga improba 



B. polaris 



Colias hccla glartalis 

 Moths Diasemia alaskalis 



I'.ucosma sp. 



1 lynaephora rossi 



llyphoraia alpina 



