BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND 26. AFD, IV. N:0 12. 33 



Arctic Exp. 1875—76), off Baffin Land (Nilsson 1894), off the 

 Atlantic coast of North America (Harger), West Greenland 

 (Hansen), as far uorth as Mnrchison Sound, lat. 77' 30' N. 

 (Peary Aiix. Exp. 1S94), East Greenland (Swed. Arctic Exp. 

 1899), Spitzbergen (Buchholtz, Swed. Arctic Exp. 1898). Near- 

 \y all these localities are situated within the cold area, and, 

 when occurring farther sonth, as along the Norwegian coast, 

 this form is only to be met with in the deepest parts of the 

 fjords, where the temperature of the water is but a little 

 above zero, and where the Gulf Stream has no influence. AVe 

 may state the same with regard to its occurrence at Spitz- 

 bergen. During the Norwegian North Atlantic Expedition 

 it was obtained onlj^ at two stations in this tract, viz., a 

 few miles S.E. of South Cape and at stat. 312, lat. 74 54' N., 

 long. 14 53' E. from a depth of 1203 m. During the Swedish 

 Arctic Expedition of 1898 I found it here at stations situated 

 more or less on the same longitude, or on the boundary be- 

 tween the cokl area and that narrow arm of the Warm- or 

 Gulf Stream area, which sweeps from Norway along the 

 West coast of Spitzbergen, some years as far north as Seven 

 Islands. Generally, it is said that this species should occur 

 nearly always in company with Eurycope gigantea, but that 

 does not seem to be the case. Only once I did find them to- 

 gether among all stations enumerated above for Muuvopsis 

 typica. But another true Arctic isopod, viz. Calatliura hra- 

 chiata, I found accompanying M. typica very often. In fact, 

 both species strikingly resemble each other, both in regard 

 to the géographical distribution, the vertical range, and the 

 bottom where they live. Both are true Arctic species re- 

 stricted to the cold area and, there living in moderate depths 

 and invariably on muddy bottom. When occurring farther 

 south, they dwell at the deepest hollows, of the fjords, and 

 never attain their full size. Compare above p. 19. Accord- 

 ing to Särs, the Norwegian specimens of M. typica [adult 

 raales] are only of the length of 11 — 12 mm. 



Length of male (from stat. 25, Exp. 1899) . 18 mm. 



Breadth » » 6 ' 



Length » female 15,5 » 



Breadth » » 7 > 



Colour above somewhat light chestnut-brown, the seeond 

 pair of antennfE and the third and fourth pair of pereiopoda 



3 



