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misleading, and there is probably great individual variation. 

 Such information as we want can only be got by con- 

 tinuous work at sea, tow-netting and trawling periodically, 

 as Mr. Dawson proposes to do with the new steamer, 

 supplemented by work in the laboratory in determining 

 the exact condition of the reproductive organs and in iden- 

 tifying the ova and larvae of the fish. 



Another important matter is the movement of the fish 

 throughout the year in our area, and the valuable statistics 

 which Mr. Dawson has been able to collect already throw 

 same light upon that. There seems no doubt that here, 

 as they have found in Scotland also, the Plaice, and 

 probably other fish, spawn at considerable distances from 

 the land, well outside the 3 mile limit, on off-shore banks. 



The advantages to a species of fish producing pelagic 

 eggs in spawning over a bank far out from land are 

 obvious. There is less chance of the embryonic and larval 

 stages being washed ashore; without being in too deep 

 water, they are removed from the many dangers of a 

 coast ; they are more likely to be in water of suitable and 

 fairly constant specific gravity ; and there is more chance 

 of the larval stages finding suitable nutriment in the 

 embryos and other young stages of the numerous inver- 

 tebrata which frequent such banks, and which rise up 

 from bottom to surface in their younger stages and sink 

 down again to bottom in later stages, so giving the young 

 fish in the intermediate waters two chances at their prey. 

 It is only then at a somewhat later stage of the early life 

 history that the young Plaice, &c, come into the shallow 

 inshore waters which we talk of as " nurseries." There is 

 then both a vertical circulation, from near the bottom (as 

 ova) up to near the surface (as embryos and larvae) and 

 then down again (as immature fish) to the bottom, and 

 also a horizontal circulation, from the offshore spawning 



