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extremes between which the spawning elsewhere has been shown to take place. There is 

 in this connection every reason to call attention to the agreement between St. 15 on 

 Eockall Bank and St. 10 in the coastal water W. of the Hebrides on the one hand and 

 between the stations 14 and 17 round Eockall Bank and St. 11 outside the coastal water 

 W. of the Hebrides on the other: at the first mentioned places, the temperature and 

 salinity at which were comparatively low, the eggs and fry of the cod were found, while 

 they were lacking at the latter places, where the temperature as well as salinity were 

 higher. In the peculiar circumstance that the temperature and salinity locally 

 are low on Eockall Bank itself, as shown by us, we must therefore seek for an 

 explanation of the fact that the cod is able to propagate here in the midst of a sea- 

 territory where the temperatures as well as salinities are generally higher than the maximum 

 values for the propagation of this species. 



2. Coalfish {Gad. virens). 



Taking into consideration that the investigations were made so late as in the last 

 half of May, the quantity of pelagic fry of the coalfish obtained W. of Scotland, occa- 

 sionally amounting to 45 and 66 specimens per ^h hour, may be said to be very con- 

 siderable; in fact, the investigations confirm the supposition previously expressed, that 

 large quantities of the fry of the coalfish are produced in the waters W. of Scotland (see 

 p. 41). Owing to the great depths in Eockall Channel the fry of the coalfish were lacking 

 there, but on the Bank itself a single specimen was obtained, thus proving that the pro- 

 pagation of this fish may at any rate take place out there, even though we do not thereby 

 learn on what scale the propagation proceeds. We did not catch the coalfish in our hauls 

 with the otter-trawl on the Bank, but according to kind information from Mr. George 

 Moody of the Grimsby firm Moodys & Kelly, which has several trawl-steamers fishing on 

 Eockall Bank, the coalfish is caught there "in large quantities at certain seasons", and 1 

 have learnt that fishing-steamers from Aberdeen have made the same experience (in- 

 formation received through Denmark's fishery-agent in England, Capt. A. Selling). 



3. Pollack {Gad. poUachius). 



At the stations inside the 200 m. curve W. of Scotland the young fry of the pollack 

 were found everywhere, sometimes in great quantities, e. g. 148 and 36 specimens per ^h 

 hour, thus showing the ample production of this species there. On the other hand, it 

 was completely lacking at our stations in Eockall Channel and on Eockall Bank, nor did 

 it appear in our hauls with the otter-trawl. Consequently, it looks as if this fish does not 

 spawn on Eockall Bank, but I cannot express an absolutely certain opinion on this matter. 



I avail myself of the present opportunity to point out, that these investigations W. 

 of Scotland have also distinctly shown that of the three above-mentioned species the coal- 

 fish spawns earliest, then comes the cod and lastly the pollack. This is easily seen from 

 the different sizes of the fry as also from the measurements given in the tables for these 

 stations (see Stat. 2— 11, 1908). 



4. Polar cod {Gad. saïda). 



This fish did not occur here, of course, nor were its pelagic or bottom stages to be 

 found at Iceland. 



5. Haddock {Gad. œglefinus). 



The eggs (determined by hatching) and young pelagic fry were found in very large 

 quantities inside the 200 m. curve N. and W. of Scotland as also on Eockall Bank, where 



