Collembola 9 \ 



slanting backward; absent on the anterior and posterior regions of the inter- 

 mediate body segments; (2) fewer setae, suberecl or curving forward; (3) long 



slender outstanding sensory seta?. Length, 1 .5 mm. 



The specimens collected by the Expedition agree with my European exam- 

 ples of the species. 



Folsomia quadrioculata occurs on damp ground under stones, wood or fallen 

 leaves, in humus and in moss, under loose bark, in flower pots, and on the sea- 

 shore under driftwood, stones or seaweed. The species is easily recognized by 

 its broad body, characteristic dirty grey colour and slow movements. When 

 disturbed it springs actively, in spite of its short furcula. In Finland it winters 

 full grown and comes to life now and then on mild days; never appearing on 

 the snow, however, but remaining among leaves or in moss in the woods (Lin- 

 naniemi, '12). 



This species, one of the commonest collembolans in northern and middle 

 Europe, has been reported from the following Arctic localities: Nova Zembla, 

 Spitzbergen, King Charles land, White island, Bear island, Jan M'ayen and 

 Greenland. 



From Canada, I have received specimens recently from Mr. Charles Mac- 

 namara, taken by him in dead leaves, October, 1917, at Arnprior, Ont. 



In the United States, the species has been recorded from Minnesota by 

 Guthrie, some of whose specimens I have studied through the courtesy of Prof. 

 Henry F. Nachtrieb. 



Bernard harbour, Northwest Territories, on the surface of a pond. June 

 18, 1915 (2 specimens), July 9, 1915 (1 specimen). F. Johansen. 



Isotoma viridis Bourlet. 

 Plate 6, figs. 48-52. 



Isotoma viridis Bourlet, 1839. — Gervais, 1844. — Nicolet. 1847. — Lubbock, 

 1873.— Parona, 1879, 1883— Schott, 1891. 1894, 1902.— Dalla Torre. L895. 

 Renter, 1895.— Lie-Pettersen, 1896, 1898, 1907.— MacGillivray, 1896.- -Meinert, 

 1896— Schaffer, 1896, 1900a, 1900b— Poppe and Schaffer, 1897. — Scherbakbv, 

 1898a, 1898b, 1899a.— Carl, 1899, 1901.— Absolon, 1900.— Carpenter and 

 Evans, 1899.— Evans, 1901a, 1901b.— Wahlgren. 1899a, 1899b, L900a, L900b, 

 1906a, 1906b, 1907, 1909.— Kieffer, 1900.— Skorikow, 1900— Willem, L900. 

 Borner, 1901a, 1903, 1906.— Folsom, 1902.— Krausbauer, 1902.— Voigts, L902. 

 Agren, 1903, 1904.— Axelson, 1903, 1904. 1905a, 1906.— (Axelson) Linnaniemi, 

 1907, 1909, 1911, 1912.— Guthrie, 1903.— Carpenter. 1907. Collinge, L910. 

 Collinge and Shoebotham, 1910. — Shoebotham, 1914. 



Isotoma caerulea Bourlet, 1839. — Gervais, IS 14. 



Desoria virescens Nicolet, 1841. — Gervais, 1844. 



Desoria cylindrica Nicolet, 1841. — Gervais. 1X4 I. 



Desoria. viatica Nicolet, 1841. — Gervais, 1844. 



Desoria pallida Nicolet, 1841. — Gervais, 1844. 



Desoria ebriosa Nicolet, 1841. — Gervais, 1844. 



Desoria annulata Nicolet, 1841. — Gervais, 1844. 



Podura viridis Bourlet, 1843. 



Podura annulata Bourlet, 1843. 



Heterotoma chlorata Gervais, 1844. 



Isotoma Desmarestii Gervais, 1S44. 



Isotoma virescens Nicolet, 1847 



Isotoma cylindrica Nicolet, 1847. 



Isotoma viatica Nicolet, 1847. 



Isotoma ebriosa Nicolet, 1847. 



Isotoma annulata .Nicolet, 1847 . — Lubbock, 1ST:'.. -Parona, L883, 



Isotoma anglicana Lubbock, 1862, 1873 



