— 164 — 



cocneivable for the few others of the species of the northern group which occur according 

 to MoKEAD and others more or less rarely in the Bay of Biscay, though we did not find 

 their pelagic fry there (e. g. coalfish and cod). 



Further, the direction of the currents in the Bay of Biscay itself will cause the 

 pelagic fry produced in the northern part of the Bay to be carried towards the south (cf. 

 the Chart IV and Vll with Moreau's statements (1. c.) that both the whiting and ling, the 

 latter however rarely, occur on the southernmost part at the west coast of France). 



E. Comparison between the Atlantic and neighbouring waters 



It may be of interest, finally, to draw a comparison between the Atlantic and neigh- 

 bouring waters such as the Mediterranean and Norwegian Sea, so far as the conditions 

 with reference to the spawning of the gadoids are known there. I may remark first of all 

 that the Mediterranean is one of the warmest and saltest seas in the world, in which the 

 temperature even in the greatest depths (more than 4000 meters) does not sink below 13°, 

 whilst the Norwegian Sea as we have already seen (p. 136) has already negative tempera- 

 tures and a salinity of less than 35*00 "/oo ^ at a depth of 600 meters or less. The At- 

 lantic has therefore an intermediate position between these two seas. 



We can understand the conditions with regard to the spawning of the gadoids from 

 the following summary ^ (cf. the grouping on p. 148 where the terms shallow-water and 

 deep-water species, "northern" and "southern" groups are defined). 



Where spawning of our gadoids takes place 



Mediterranean Atlantic Norwegian Sea 

 Shallow-water /""northern" group -4- -j- -|- 



ll"s 



species (groups a and b) I "southern" group 



eep-water f "northern" group 



species (group c) I "southern" group 



towards the outer conditions during the spawning time, whilst these in other stages are much less parti- 

 cular and are therefore much better able to stand both lower and high temperatures than those required 

 whilst spawning. 



' There are however small areas locally in the Norwegian Sea along the Norwegian coast where 

 the conditions are different, e. g. in several of the characteristic Norwegians fjords where the depth may 

 be over 1000 meters and the hydrographical conditions . resemble greatly those in the Atlantic south of 

 Iceland. In deep water here we find temperatures of 6°— 7° and salinities of over SS-lO^ioo thus quite 

 different from in the Norwegian Sea (see 0. Nordgaard : Hydrographical and Biological Investigations 

 in Norwegian Fjords , p. 19, Bergen 1905 ; according to whom a temperature of 6'3° and salinity of 

 35'11 "loo and a temperature of 6'3° and salinity of 3514 "loo were found even in the far north Tys and 

 West Fjords (N. of the Polar Circle at 68° 12' and 68° 15' N. L.) in respectively 700 and 630 meters). 



^ Information with regard to the Mediterranean from which I have myself seen specimens of Merliiccius, 

 G. Po'utassou, luscus and argentetos as also of Molva elongata has been taken from Kaffable 1. c, from 

 Marion (Annal, du Musée d'Hist. Nat. de Marseille, tome IV, lere section, 1890) and from Holt (ibid, 

 tome V, No. 2, 1899). The available data are not always quite complete, as there is some disagreement 

 amongst the various authors with regard to which of our species occur in the Mediterranean, but on the 

 whole there is no doubt about the correctness of the above summary. 



In connection with this I may mention, that according to Johiian and Evekmann: Fishes of 

 North and Middle America, vol. Ill, 1898, only the species belonging to our "northern" group (ff. cal- 



