20d Canadian Arctic Expedition, 1913-18. 



1877. Idotaega longicauda Lockington, Proc. Cal. Acad. Sci., VII, Pt. 1, p. 45. 



1877. Idotea entomon Meineht, Nat. Tidsskr. (3), XI, p. 84. 



1880. Idotea entomon Brandt, Comptes Rendus, p. 713. 



1880. Idotea entomon Brandt, Ann. Mag. Nat. Hist.,. VI., p. 98. 



1883. Glyptonotus entomon Miers, Journ. Linn. Soc. London, XVI, pp. 12-13 



pL 1, figs. 1-2. (See Miers for further synonymy). 

 1899. Glyptonotus entomon Richardson, Proc. U. S. Nat. Mus., XXI, p. 843. 

 1899. Glyptonotus entomon Richardson, Ann. Mag. Nat. Hist. (7), IV, p. 262. 

 1905. Mesidotea entomon Richardson, Bull. 54, U. S. N. M., p. 348, figs. 374 



a-m. 



Range: This magnificient species is definitely recorded from the Kara sea, 

 westward across polar Europe and America, the Bering sea, and it is not improb- 

 able that future explorations will prove it a resident of the remaining polar area, 

 Siberia. Its present known southern range establishes it in the Cattegat, 

 Denmark; Labrador, the east coast of North America; Pacific beach, California, 

 the west coast of North America and Avatcha bay, Kamchatka, Asia. 



The material listed herewith was secured by the Canadian Arctic Expe- 

 dition : 



Mesidotea entomon (Linnaeus). 



Station 20b-c. Grantley harbour, Alaska, 2-3 fathoms; sandy mud with 

 algce; July 30, 1913. 4 specimens. 



Station 24. Sandspit at point Barrow, Alaska; August 22, 1913; 2 adult 

 specimens. 



Station 27a. Collinson point, Alaska; 1 fathom; gravel, no vegetation; 

 September 7, 1913. 7 specimens; from stomach of (white-fish ?). 



Station 27c. Collinson point, Alaska, 18 inches of water; sand and gravel, no 

 vegetation; September 18, 1913. 1 adult specimen. 



Station 27i. Lagoon at Collinson point, Alaska, pelagic under five-inch 

 ice; depth 3-4 ft.; September 18, 1913. 13 immature specimens. 



Station 27j. Collinson point, Alaska; September 7, 1913, from stomach of 

 Phoca foetida. 2 immature specimens. 



Station 27s. Collinson point, Alaska, 3 fathoms; mud and gravel; October 

 3, 1913. 12 specimens, adult and immature. / 



Station 27y.^ Entrance to lagoon at Collinson point, Alaska; October 8, 

 1913, (no ice). 2 immature specimens. 



Station 28a. Collinson point, Alaska, on sea bottom; mud, sand and green 

 algae, 1 fathom; October 14, 1913. . 3 adult specimens. 



Station 28d. Collinson point, Alaska, on sea bottom; IJ/^ fathoms, gravel, 

 sand and green algce; October 18, 1913. 9 adult specimens. 



Station 281. Collinson point, Alaska, sea-shore; September 8, 1913. 1 

 adult specimen. 



Station 28to. Collinson point, Alaska, July, 1914. 1 adult specimen (dry). 



Station 28o, Stomach contents (samples from 10 Salvelinus malma Wahl.) 

 from Collinson Point, Alaska; July 8, 1918. 6 young. 



Station 28r. Part of stomach contents of 2 female Cottus quadricornis from 

 bay at Collinson point, Alaska, July 24, 1914. 2 adult specimens (mutilated). 



In connection with the above stations (27 and 28) Mr. Johansen notes: 



"The young ones of Idothea sp., which are so common in the shallower parts 

 of the sea up here (see specimens kept) are found pelagic in the water while the 

 older Idothea (if they are the same species) are bottom-forms. These young 

 stages swim in circles in the water with the ventral side upwards ; or they ascend 

 to the surface in a sloping line from below. During this they ' row ' by trans- 

 versal strokes with their long body-legs, while the foliaceous, abdominal legs are 

 not used for swimming, but support the outspread tail end (telson) which serves 

 as a 'rudder.' These young Idothea have thus a very strange appearance when 

 swimming." 



