— 16 — 



found, and from this it follows again with certainty, that the polar cod is able to 

 reproduce at Iceland. But though this is certain, it is likewise true that the repro- 

 duction cannot proceed on any very large scale, as if this were the case we should not 

 have missed taking its pelagic young in all the numerous hauls made in the course of 

 the three years, 1903 — 04—05, at those parts of Iceland where the water is so cold that 

 we might have expected to find them. 



If we consider where we found the older stages of the polar cod, we see that they 

 point in the same direction. The adult polar cod occur along with similar stages of the 

 cod (Gadus cßUarias) in shallower depths at the coast right to the margin. But whilst 

 the number of cod we have taken and examined at Iceland can be counted not merely 

 in thousands but in hundreds of thousands, we have in all the three years (1903—05) 

 only caught 6 — 7 polar cod, most of which were taken on the east coast, a single specimen 

 on the north and north-west coast, but absolutely none on the south or west coast.' 



We thus see that the polar cod only occurs in quite the coldest parts of the region 

 investigated by us, i. e. at the eastern and northern coasts of Iceland. But even here its 

 occurrence is of so sporadic a nature, that there can be no doubt from this alone that we 

 are here at the boundary of the distribution of the species. The true home of the polar 

 cod is the Polar Sea, on whose ice-covered coasts (Greenland, Spitzbergen, White Sea, 

 north coast and islands of Asia) it occurs according to available information in great 

 quantities, and it was the fish which Pm-rmoF Nansen found furthest north on his famous 

 expedition. 



As described already (Gadus. Part I, p. 28), it keeps not only to the ice-bound coasts, 

 but also follows the polar ice when drifting. By this means it may be carried out even 

 over the greatest depths ^ and thus comes to lead a half pelagic life, though still following 

 the ice and feeding upon the characteristic fauna of coastal forms which is bound to this. 



From this basis we can, I believe, better understand the sporadic occurrence of the 

 polar cod on the northern and eastern coasts of Iceland. We know indeed, that these 

 coasts are often covered with polar ice, which in certain years may even persist far into 

 the summer, whilst in other years there is but little of it. One of the places where the 

 ice usually first appears, is the neighbourhood of Cape North, the north-west promontory 

 of Iceland. Ice was present here for example in June 1903, when the "Thor" was working 

 in these waters, whereas in 1904, although we sailed twice round the Island in April and 

 in May— June, we saw not a trace of ice. Our discoveries of the different developmental 

 stages of the polar cod seem to agree very well with this, as it was only in 1903 that 

 the just hatched fry were taken and only at a single station, somewhat east of Cape North. 

 Here we had 14 days earlier met with the polar ice, and at the same station where we 



> The following specimens of medium-sized and adult Gadus saîda were taken by the "Thor": 1 

 spec, of 19 cm. at Akureyri (north coast), 17. Aug. 1904; 1 spec, of 20 cm. in Patriks Fjord (N.W. coast), 

 22. .Tune 1904; 2 spec, of 10 and 11 cm. in Eski fjord (E. coast), 30. April 1904; 1 spec, of 20 cm. in 

 Eeydar Fjord (E. coast), 10. Aug. 1904; 1 spec, of 19 cm. in Seydis Fjord (E. coast), 19. .July 1904. Further, 

 I saw a somewhat larger specimen taken in Seydis Fjord in 1904. AH these specimens were taken in 

 1904, none in 1903 and 1905. 



^ With this also agrees the discovery described by Ad. Jensen (Meddelelser fra Kommissionen for 

 Havundersegelser. Serie Fiskeri, Bind I, Nr. 7, 1905) of the otiliths of the polar cod in bottom samples 

 from great depths to the north of Iceland. 



