— 42 - 



There can be no doubt that both Holts specimens of the 2nd of May and ours of the 

 25th must have been hatched very early in the year, probably in February or in January. 

 At Valencia in the middle of June a haul to the land with the eel seine from 9 meters 

 gave no less than 143 young coalfish (the majority of which had a length of 6— TVa cm., 

 see List, p. 31). 



We may conclude from this as from Holt's observations on the young bottom stages, 

 that the coalfish spawns on no small scale at Ireland, although there is no 

 question of such large quantities as at Iceland and especially the Faeroes. 



4. North Sea 



Our North Sea investigations fall partly in April partly in the beginning of May (as 

 also in later months), and thus at a time of year favourable to obtaining the pelagic young 

 of the coalfish. It will be seen from Chart II, that the distribution of the pelagic fry of 

 the coalfish is very different from that of the cod ; whereas the latter occur everywhere 

 in the North Sea, the fry of the coalfish are restricted in their occurrence to 

 the deeper and salter northern and western parts and are lacking in the east- 

 ern and southern parts. We have taken large quantities of the pelagic fry of the coalfish 

 in the northernmost parts of the North Sea, especially in the neighbourhood of the 200- 

 meter line N. E. of the Shetlands, where the number per '/2 hour's haul mounted up to 

 272. It will be seen from the Chart and also from the tables, that the numbers here on 

 the whole compare well with those found at Iceland and the Faeroes. 



Whilst the cod spawns in quantities in the inner Danish waters (Kattegat and Belt 

 Sea), the eggs and the pelagic fry of the coalfish are never found there, and even in the 

 Skager Rak where the eggs and the fry of the cod are also found in numbers, we have taken 

 no pelagic coalfish fry^. The reason for this difference in the distribution of the pelagic fry 

 of the cod and the coalfish in the North Sea, Skager Kak and the Danish waters must be, 

 that the coalfish requires deep er water for spawning than is found in the shallow 

 southern and eastern parts of the North Sea and the inner Danish waters, whilst these are 

 sufficient for the cod. This cannot explain the absence or scarcity of the pelagic coalfish 

 fry in the Skager Rak with its considerable depths, and in this case we may consider that 

 the coalfish requires a higher salinity and temperature than are to be found there during its 

 spawning time (in the first part of spring) ; the conditions at Iceland where the coalfish 

 only reproduces in the salt and warm Atlantic waters may be recalled here. These two 

 moments, the low salinity and temperature, also apply however to the southern ^ central 

 and eastern parts of the North Sea, and are undoubtedly contributory to the fact that the 

 coalfish practically never spawns there. I shall however not enter further into the condi- 

 tions in the North Sea, which will undoubtedly be thoroughly discussed by Dr. Damas (see 

 his report) but restrict myself to the remarks above, as they are of interest in comparison 

 with the conditions in the Channel. 



' My colleague, Dr. A. U. Johansen, who has worked a good deal with the "Thor" in the Skager 

 Rak in early spring, informs me that he has taken no pelagic fry of the coalfish there. 



^ "With exception of the most southerly part nearest the Channel from which water of high salinity 

 and temperature enters the North Sea. 



