Insect Lift on the Western Arc ist of America 23k 



May 11-20, 1916 



The first fly was noticed on May L8 and on the aame day a large probably 

 hibernating) parasitic wasp (Icheumon suturalis) and collembola, miti 

 decipiens), small spiders, caterpillars, beetle larvae, carabids A 

 pennis, etc.), all under loose, flal stones. Two of these caterpillars were ob 

 on July 11 to be parasitized by hymenopterous larvae; three othei pillars 



pupated July 13-20. 



May 21-31, 1916 



Many flies were out on May 21, both the bis bine and two smaller speci 

 carabid beetles, spiders, and an ichneumonid wasp were noticed on this day, and 

 the common collembola, spiders, mites, caterpillars, and dipterous larvae. II 

 dipterous larvae (Tipula arctica, etc.) were placed for rearing (No. 106) and 

 made galleries in the sand in the jar before pupating in June. Parasitic 

 hymenopterous larvae were noticed in one of the crane-fly larvae, but efforts to 

 rear it were unsuccessful. Four adults {Tipula arctica) emerged -Inly 7. One 

 species of caterpillar was about 1 cm. long, and occurred in numbers crawling 

 on a snow-free, dry sand dune near the beach. These larvae had perhaps hil 

 nated and they made their cocoons in June. One of the big spiders tLn<-<>sa s] 

 was caught on May 31 in its funnel-shaped web. The mouth of tin- web was 

 about 2 cm. in diameter. 



The usually warm weather favoured the development of insect lite in fresh 

 water; collembola (Isotoma palustris, Sminthurides aquaticus, etc.)) surface- 

 spiders, copepods, dytiscid beetles (Colymbetes dolobratus) and mites <<<ilunina 

 hums) were observed. Freshly-hatched mosquito larvae (Aed<y sp.) 2-4 nun. 

 long, were noticed on May 31, or eighteen days earlier than in 1915. On tin 

 same day various dytiscid beetles (Hydroporus sp., Colkunhus unguicularis, 

 Agabus nigripalpis) , oligochaete worms {Henlea sp.) were also seen, as wer< 

 tipulid (?) larvae, midge larvae, and the empty puparia of Mydaeina <>hscnra. 



May 21-31, 1915 

 The following additional insects were noted : 



Carabid beetles (Amara hmnatopn) 



Spiders (see above). 



Weevils ( ' richalophus st&fanssoni) 



Flies (.Phormia coerxilea and a minute "jumping" fly) 



Parasitic insects are not greatly influenced by weather and it is, therefore, 

 unnecessary to deal with them under monthly subdivisions. < Observations w< 

 made of the two diptera that infest the caribou. All efforts to rear these grubs 1 

 from larvae were unsuccessful, although several methods of rearing were tried. 

 .Some of the almost full-grown larvae were placed on fresh caribou meal . some in 

 bits of caribou skin with larvae in situ, some in a jar with sand, and even a whole 

 caribou skin containing grubs was rolled up to prevent drying. The grubs were 

 never brought through the pupal stage, although some were kept for more than 

 a year. The field observations agree with the accouni given by G. M. Douglas 

 on the caribou between Great Bear lake and Coppermine river. 1 



Two female adults 2 were caught al Bernard harbour July 11. 1916. Thegrubs 

 in the caribou skins examined at the end of May. L915 and L916, were very 

 numerous and all big. Only two, not full grown, larvae 1 22 nun. long) were found; 

 they were wholly white except the light brown fringes of body -pines and the 

 dark brown, apical head dot and terminal spiracles. All the other larva' were 

 from 25 to 30 mm. long; the younger (smaller) of these had the chitinoue heel, 

 the terminal spiracles, and the body-spines dark brown, and fine dots of lighter 



i Douglas. G. M., ''Lands Forlorn," 1914, p. 191; photograph of gr\x\ ikln. 



p. 192. 



- (Edemagena tarandi (Linne). 



