38k 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.' 



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 Jiemiptera, 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 {Atrcpos and Troctes, 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, and hemiptera depend on 

 land vegetation but most of the neurbpteroids^ 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 " Neuropteroids " 10 



40 " Suctoria " 6 



40 " iSiphunculata " 6 



25 " Physopoda only 1-2 



13 " Orthoptera " 1-2 



65 " 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.' No orthoptera have been found in the 

 Canadian Arctic archipelago. From the Arctic mainland the only grasshoppers we 

 secured were a specimen of Acrididse, 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. Stefanssofa 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 Elxpedition." Meddelelser om Groenland, vol. 43, p. 55. 

 "The insects of East Greenland," Meddelelser om Groenland, yol. 29, pp. 3i6i6-369. See also 

 W. Lundbeck: "Bntomolog Undersog. i West Groenland, 18S9-9'0'," Meddel. om Groenland, vol. 

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

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

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



T. C. SchiSdte "Gronlands Land — , Perskvands — og Strandbreds— Arthropoder," in Rink 

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



2 Trichoptera are the only neuropteroids known from the east coast. 



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



