The Isopoda of the Canadian Arctic and Adjoining Regions. 



By P. L. Boone 



Aid, Division of Marine Invertebrates, U. S. National Museum 



The Isopod Crustacea secured by the Canadian Arctic Expedition represent 

 four species of well-known polar forms; namely, Arcturus baffini Sabine, 

 Mesidotea entomon (Linnaeus), M. sabini (Kr(/)yer), Munnopsis typica M. Sars. 

 Mr. Frits Johansen's field notes present interesting data on the life history of 

 some of these species and I have therefore incorporated them verbatim in the 

 following list. 



In the collections of the Victoria Memorial Museum at Ottawa are several 

 lots of Isopoda secured in the Arctic regions by the "Diana," "Neptune" and 

 other expeditions. It has been thought advisable to include, the records of 

 these specimens in this report. 



The collections of the U. S. National Museum contain valuable collections 

 of Arctic material; namely, that secured by Dr. William H. Dall during his 

 explorations in Alaska from 1865 to 1885, collections from the U. S. Bureau of 

 Fisheries, the U. S. Department of Agriculture, the Revenue Marine, members 

 of the Navy, Army and various individual collaborators, also material secured 

 by gift or exchange from other institutions, which has likewise been examined 

 and included in this report. 



On the whole, though the collection is not remarkably large, it is probably 

 the largest and most complete for the Alaskan-Canadian Arctic region ever 

 brought together.' 



The following annotated catalog is intended to contain a list of all the species 

 known to inhabit the designated region with the addition of a few which approach 

 the boundary so closely and whose affihities are Arctic, rather than boreal, that 

 it is highly probable that on further search their range will be found to cross it. 



It is intended that the synonymy cited shall be comprehensive, giving 

 references to the original description, to good figures, and to the data of geo- 

 graphical distribution which has necessarily been taken from the literature. The 

 material examined by the writer embraces the entire collections of the Victoria 

 Memorial Museum and the U. S. National Museum; but in many cases it has 

 been necessary to take the data from the literature, especially that of the early 

 writers, and it follows that the present writer assumes no responsibility for the 

 identification of species so derived. Usually, however, there is no particular 

 reason for doubting the accuracy of these identifications, except in a very few 

 cases, to which attention is directed in connection with the discussion of the 

 species involved. 



The object of this work is to sum up the known Isopod fauna of arctic 

 North America. This has involved an examination not only of the species 

 obtained within this area, but also of the adjacent region to the west, east and 

 south. Theresult is that the work includes a summary of our present knowledge 

 of the Isopoda for that -region of North America limited on the Alaskan shore 

 line to the winter line of floating ice and passing southward indefinitely in deep 

 water; northward embracing arctic Alaska and Canada and restricted on the 

 east Canadian coast to the 60° parallel. In considering the very interesting 

 complex of the Davis strait fauna, I have followed Dr..H. J. Hansen's masterly 

 treatment of the area, and include in my report only those species which haye 



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