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ascribe importance to the negative results, and with much else I have had splendid con- 

 firmation of this in finding the same distribution for three years running of the cod young 

 in the waters round Iceland. 



On account of our constant use of the capable young-fish trawl in these investiga- 

 tions, there can be no doubt that the Chart PI. X gives an essentially correct picture of 

 the distribution of the eel larvae in the waters investigated during the "Thor's" Atlantic 

 cruises. 



It has to be said with regard to many of the stations marked on the Chart by 

 one spot, that we have there made observations several times at différent times of the 

 year or in different years. Thus, for example, the stations betwen Iceland and the 

 Faeroes were visited both in May and August in the three years (1903 — 1905), these 

 being the stations where the regular hydrographie seasonal investigations were made. 



It will be seen from the Chart that we have taken the eel larvae right from the 

 Faeroes southwards to the coast of Brittany. Our investigations do not extend 

 any further to the south, so that I am not able to report anything upon the distribution 

 off southern France and the Spanish peninsula. On the other hand I consider that the 

 waters further to the north, around Iceland, have in the main been sufficiently invest- 

 igated in this regard. 



A study of the distribution of the eel larvae has shown me, that various factors 

 determine this, namely (l)the depth, (2) the hydrographical conditions, as the eel 

 larvae were restricted in their occurrence both over certain depths and in accordance with 

 certain hydrographie conditions. In addition to these two factors others also seem to be 

 of importance for the quantities of eel larvae present, thus especially (3) the situation of 

 the place relative to countries more or less rich in eels. 



In the following pages I shall consider each of these separately. 



(1) Importance of the depth. If we examine the Chart, Plate X, we see that 

 the eel larvae are found over the whole stretch from the Faeroes to Brittany in the neigh- 

 bourhood of the 1000 meter line, in greatest numbers apparently between this and the 

 2000 meter line. If the red points on the Chart indicating the places of discovery were 

 connected by a line this would in the main follow the 1000 meter line. 



Closer investigation of the depths, over which the eel larvae were found, shows that 

 most of the places of capture lie over depths greater than 1000 meters, even though on 

 the other hand the larvae were also found over ca. 800— 900 meters. This experience 

 was also quickly learnt on board the "Thor". If we wished eel-larvae, we must not 

 come into shallower water than 800 meters. This was confirmed by many hauls with 

 the young-fish trawl, both those which gave no eel larvae and those in which they were 

 taken in quantities. 



We thus see from our investigations, that the depth is of greatest importance for the 

 occurrence of the eel larvae. We shall see later that the earlier discoveries of the larvae 

 in the Atlantic and Mediterranean confirm our results. 



use of this apparatus in the most different waters has convinced me of its great fishing qualities. As evidence 

 of this to those who have some knowledge of the fishing capacity of different apparatus, I may mention that 

 I have taken in a single 1/2 hour's haul over 1200 cod young (Gadtis cal/arias) of ca. 3 — 5 cm. in length 

 as well as many other fish young at the end of July 1905 at the Faeroes. If we reflect how rapid the cod 

 young of this size are in their movements, the result mu.st he considered unique. 



