APPENDIX G — 4 — 



In this respect, the international investigations have been able to build upon the results of 

 earlier expeditions. The Wyville Thomson Expedition and the Danish Ingolf Expedition have 

 collected valuable information concerning the North Atlantic Ocean. From the earlier English 

 and Scottish investigations also, we have numerous data concerning the distribution of the fish- 

 fauna in the different parts of the North Sea. The investigations of recent years have rendered 

 it further possible to collect a much more comprehensive material; and much more information 

 especially could be gathered concerning the fishes, because apparatus was for the first time 

 employed, calculated to make larger catches than those used by earlier expeditions; also, the 

 endeavour has been made, in connection with the hydrographical investigations, to procure 

 systematic information concerning the physical relations under which the fish taken lived. 



We shall therefore begin the following description of the principal results attained hitherto 

 from the international fisheries investigations, with a survey of the geographical information 

 which exists concerning the general distribution of the fishes within the region under investigation. 



1) The deep basin, which occupies the entire central portion of the 

 Norwegian Sea, has depths as great as 3700m. in its centre, and by far the greatest 

 part is more than 200 m. deep. Towards the east, south and south-west, this deep-sea basin 

 is bounded by banks wliich, in spite of many depressions and elevations in the sea-bottom, form 

 a continuous surface from Spitzbergen to the Denmark Straits and slope down towards the 

 great depths of the Norwegian Sea. 



The numerous hydrographical investigations of the years 1900 — 1904 have shown, that the 

 great masses of water occupying the central portion of the Norwegian Sea possess an uniform 

 character. All water-samples from depths of 1000 to 3000 m. showed the same salinity and 

 the same temperature both in summer and in winter ; namely, on an average 34,92 "/oo salinity 

 with a variation of 0.04 "/oo, and a temperature varying between — 1.1° to — 1.2°. 



A glance at the chart of depths (Plate 1) gives us a picture of the distribution of the 

 cold bottom-water in the Norwegian Sea. The depths over 600 m are shown on the chart in 

 various shades of blue. We may say in general, that the region of the Norwegian" Sea marked 

 by the blue colour has everywhere cold water at the bottom, otherwise all the coastal banks, 

 distinguished by brown colour, are covered by warmer water. 



It has been concluded from the homogeneity of these water-masses, that they have but a 

 very slight movement. As to the origin of the bottom-water of the Norwegian Sea, the hydro- 

 graphical investigations have led to the conclusion, that it arises from the wide region between 

 Jan Mayen and Spitzbergen, where the bottom-water rises to the surface and where the salinity 

 and temperature are the same as at the bottom further south. 



Numerous fishery investigations, by means of which endeavours have been made to learn 

 the fish-fanna of the deep basin, have shown that the same characteristic forms obtain from the 

 southern Shetland-Fseroe Channel to as far north as Spitzbergen, namely: 



