_ 5— .TOH. H.TOKT ANii ('. U.JOH.PETERSPIjS' 



Cottidœ: Cottunculus microps, subspinosus. 



Liparidse: Oareproctus Reinhardt!, Paraliparis bathybii. 



Ophidiidss: Eliodichtliys regina. 



Lycodinse: L. muraena, flagellicaiida, frigidus, pallidus, similis, eudipleurostictus, seminudus. 



the sliark: Somniosus microcephalus and 



the ray: Raja hyperborea. 



The earlier statements, that this fauna was present only in sparse quantities, have not quite 

 been confirmed. Thus, for example, on the ■29"' of August 1901, at 63°13' N. L., 6°32' W. L. 

 we obtained 34 Paraliparis bathybii, 1 ßhodiclithys regina and 17 Lycodes frigidus in a two 

 hours haul with a large trawl of 50 foot head-line at 1735 m. depth. Similar good catches 

 have also been made in the Shetland-Fseroe Channel; further, to the east of Iceland at 

 66°20.5' N. L., 12°10' W. L. the Danish investigation-steamer "Thor" obtained 4 Eaja hyper- 

 borea, 1 Somniosus microcephalus and 20 Hippogiossus hippoglossoides on 225 hooks at a depth 

 of 855 m (bottom-temperature — 0.60). 



Thorough investigations to determine the limit of this deep-sea fauna in the upper layers, 

 showed that it could be sharply defined. Thus, for example, on the 29"> of June 1902 at 

 62°32' N. L., 1°56'E.L. a long line was set out, the one end of which was at a depth of 

 390 m. and temperature of 6°.l, the other at 450 m, temperature — 0°.2; the length of the 

 line was ca. 2200 m. At the deeper end, fish of the deep sea (Eaja hyperborea) were taken, at 

 the other end, fish of the coastal banks (Sebastes, Macrurus). This limit has thus the practical 

 importance, that it marks the division between the worthless species of the Arctic and the 

 useful species of the coastal banks. With the changing of the oceanic currents this limit 

 rises or falls, so that the useful species appear higher or lower on the slope of the coastal 

 banks. Differences may also appear between different regions of the Norwegian Sea, according 

 as the oceanic currents are stronger in one or the other. We should especially expect, to find 

 great differences where the strongest currents meet, for example at the Fœroe-Iceland ridge, 

 just as it has been found that the limit along the long slope of the Norwegian coastal banks 

 can be different at different places. 



2) We find the greatest contrast to the depths of the Norwegian Sea in the deep basin 

 of the Atlantic Ocean and on the southern slope of the great submarine ridge 

 which, from G-reenland to the North Sea, forms the boundary between the two seas. 



The hydrographical section (Fig. 1) shows the relations of salinity and temperature in the 

 ocean, above and on both sides of the Paeroe-Iceland ridge. The salt Atlantic water, which 

 presses from the south over the ridge, is brought to a sudden stop (interruption?) by mixed 

 layers, whicli come from the north. On the nortli side of the ridge, the low temperature of 

 0° lies in depths which vary between 450 to 600 m. ; the surface of the ridge is washed by 

 layers of 2°— 4", whilst the southern slopes indicate water of 6° down to a depth of 700 m. 



The Danisli Ingolf Expedition luis shown that tlie animal life, especially the lower animals, 

 is different on the two sides of the Pïeroe-Iceland ridge. Our fishery investigations liave shown 

 us that a triple fauna exists here in agreement with the hydrographical conditions, namely, the 



