38x Canadian Arctic Expedition, 1913-18 



GENERAL (ARCTIC INSECTS) 



A comparison of the insects found in the American Arctic and of those 

 found in Greenland, is interesting. Dr. I. C. Nielsen has compared the insect 

 fauna of the west coast of Greenland with that of the east coast. 1 



Owing to the severity of the climate on the east coast of Greenland as 

 compared with that on the west coast, insect life is less plentiful, including less 

 than half the number of lepidoptera, one-third that of coleoptera and hymen- 

 optera, one-fourth of hemiptera, one-sixth of diptera, and one-tenth of neurop- 

 teroids. Orthoptera and thysanoptera are only found on the west coast and 

 are represented by single species (Atropos and Trades, Forficula, Blatta, and 

 Physopus) all probably introduced. No beetles (except perhaps staphylinids) 

 are known on the east coast north of about 75 degrees north. 



With the exception of Strepsiptera, most orders of insects are represented 

 in Greenland, but far from all families. Ninety per cent of the hymenoptera 

 are ichneumonids, the remainder, sawflies and bumblebees; the beetles are 

 mainly those feeding upon plants, decayed matter, minute arthropods, or 

 waterbeetles. The hymenoptera, lepidoptera, arid hemiptera depend on 

 land vegetation but most of the neuropteroids 2 and many of the diptera pass 

 the early and longer part of their life in fresh water. Many of the diptera also 

 belong to blood-sucking species feeding upon Eskimos and other mammals or 

 upon decayed matter. Recent Danish authors give the following list of the 

 different orders of insects found in Greenland : 



Diptera about 170 species Hemiptera about 12 species 



Hymenoptera 



Mallophaga 



Lepidoptera 



Coleoptera 



Collembola 



Mites 



55 

 40 

 40 

 25 

 13 

 65 



Neuropteroids ........ '. 10 



Suctoria ............. " 6 



(Siphunculata .......... " 6 



Physopoda ............ only 1-2 



Orthoptera ............ " 1-2 



Spiders .............. about 45 



The insects of Greenland are very similar to those so far found in the Amer- 

 ican Arctic, though the eastern part of the American Arctic has a far more 

 severe climate than the corresponding degrees of latitude in the western part. 

 The limit of spruce, or of isotherms is, therefore, a better southern boundary on 

 which to base conclusions than any parallel of latitude. Owing to the intimate 

 connexion between plants and insects the tree limit is preferable, especially as 

 the data available are insufficient to warrant the use of isotherms as a base. 



The country not forested is known as the "barren grounds" and reaches as 

 close to the pole as explorers have attained. Forest insects cannot, of course, 

 invade these grounds. The next insects to stop are the grasshoppers and prob- 

 ably also the other families of orthoptera. 3 No orthoptera have been found in the 

 ( '-anadian Arctic archipelago. From the Arctic mainland the only grasshoppers we 

 secured were a specimen of Acridid*, said to have been caught near the divide 

 of the Alaskan Arctic mountains, within, or near, the limit of trees, and the 

 specimen of Melanoplus frigidus secured by Mr. V. Stefansson in the summer of 

 1911 in the vicinity of Langton bay. The absence of grasshoppers in the Arctic 

 is very noticeable and not easily accounted for. It cannot be the absence of 

 suitable food, for grasshoppers eat almost any vegetable, and vegetation is 



1 "The insects of the Danmark Expedition." Meddelelser om Gro-iil;in<l, vol. 43, p. f>5. 

 "The insects of Bast Greenland," Meddelclsrr om < Irocnhind, vol. 29, pp. 3i6'6-369. See also 

 W. Lundbeck : "Entomolog Undersog. i West Groenland, 1889-!Hi," Ah <!<!. -1. om Groenland, vol. 

 VII, pp. 139-41; and W. Lundbeck and K. Henricksen in "Conspectus fauna groenlandira, 

 Land anthropods," Meddel om Groenland, vol. 22, p. 797, 1918; and W. Lundbrrk : "Notitser 

 om GronUinds entomolog. Fauna," pp. 27-34. 



T. C. Schiodte "Gronlands Land , Ferskvancls og Strandbreds Arthropoder," in Rink 

 "Naturhist Tillaeg til en geographist og Statistisk Beskrivelse af Gronland," 1857, pp. 50-71. 



2 Trichoptera are the only neuropteroid.s known f rom the east coast. 



3 The Forficula collected on Parry's and Ross' voyages was probably introduced. 



