Collembola of the Canadian Arctic Expedition, 1913-18. 



By JUSTUS W. FOLSOM 

 Of the University of Illinois. 



This is a report on the Collembola obtained by tin- Canadian Arctic KXJM- 

 dition, 1913-16. The material, collected by Mr. K. Johansen, consisted <>f 

 numerous well-preserved specimens, in excellent condition for study, and com- 

 prised the following twelve species: 



Podura aquatica L. 

 Achorutes tullbergi Schaf. 

 Achorutes sensilis, n. sp. 

 Achorutes armatus (Nic.) 

 Onychiurus duodecimpunctatus , n. sp. 

 Tetracanthella wahlgreni Axels. 

 Folsomia quadrioculata (Tull.). 

 Isotoma viridis Bourl. 

 Isotoma palustris (Mull.). 

 Entomobrya comparata, n. sp. 

 Lepidocyrtus cyaneus TulL 

 Sminthurides aquaticus (Bourl.). 



The types and other specimens upon which this report is based are deposited 

 in the- National Collection of Insects, Ottawa. 



Podura aquatica Linnaeus. 

 Plate 1, figs. .1-3. 



Podura aquatica Linnaeus, 1758. Nicolet, 1841. Tullberg, 1871, 1872. 

 Lubbock, 1868, 1873. Packard, 1873. Parona, 1879, 1882. Dalla Torre, 

 1888, 1895. Uzel, 1890. MacGillivray, 1891. Schott, 1894, 1902. Renter, 

 1895. Schaffer, 1896, 1900a, 1900b. Lie-Pettersen, 1896 Poppe and SchiifTer, 

 1897. Scherbakov, 1898b. Carl, 1899, 1901. Wahlgren, 1899c, 1906a. 

 Carpenter and Evans, 1899. Absolon, 1900, 1901. Willem, 1900. Bonn r 

 1901a. Krausbauer, 1901. Agren, 1903. Guthrie, 1903. Axelson, 1906. 

 (Axelson) Linnaniemi, 1907, 1912. Folsom, 1916. 



Hypogastrura aquatica Bourlet, 1839. 

 Hydropodura aquatica Borner, 1901b, 1902. 

 Podura granulata MacGillivray, 1893. 



Blackish blue; antennae and legs reddish brown; furcula pale brown. 

 Head hypognathous. Eyes 8 + 8. Ocular areas with conical elevations 

 between the eyes. Postantennal organs apparently absent, represented extern- 

 ally by minute rudiments. Antennae shorter than the head, stout, cylindrical, 

 with segments about as 4:5:6:7 in relative lengths. Olfactory hairs of fourth 

 antenna! segment absent. Sense organ of third antennal segment consisting of 

 a pair of short stiff setse. Body short and stout. A dorsal subsegment occurs 

 on the anterior part of each body segment except the ninth. Unguis (fig. 1 > 

 very long, longer than the tibio-tarsus, slender, curving, unidentate behind the 



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