yellowish in colour, being perfectly camouflaged. Sometimes, however, there is an extensive 

 production of the yellow colour-cells in the form of conspicuous spots. At spawning time plaice 

 are slightly catadromous in habit and move down to depths around lb to 25 fathoms. The 

 eggs float and the larva is at first quite symmetrical. But very soon it sinks to the bottom ; 

 the migration of the left eye takes place and the young now look like flat-fishes. During their 

 early years the small plaice live in sunny in-shore waters in sandy bays called -'nursery grounds" 

 by the English. When they reach about 3 inches in length they migrate down to depths of about 

 5 to 8 fathoms. After 2 years they measure 5^ inches, and at 3 years nearly 8 inches, fn the 

 fourth year, having grown to about 9 inches, they become sexually mature for the first time. 

 Growth now slows down, a 2 foot plaice being more than 20 years old. Plaice are euryhaline 

 and eurythermal, changes in hydrological conditions having but little elTect on these sedentary 

 fishes. The amount of food ingested plays a great part in the growth of a plaice. Finding that 

 growth was poor in the littoral zone, Danish scientists transplanted such plaice to the Dogger 

 Bank, where an abundant planktonic life led to their rapid development. These fishes are much 

 esteemed in the Scandinavian countries and in the British Isles, but off the French coasts they 

 are at the southern limit of their distribution and the indilTereut (piality of their ilesh preiludes 

 their being very much appreciated. 



Fish is an important part of the diet in northern countries, whose fishing vessels are supplied 

 from this immense reservoir of li\iiig matter. \n extensixc fleet of trawlers or drifters, without 

 counting the small boats of the in-shore fisheries, ranges over the grey waves of the northern .seas. 

 Herring nets measuring several miles drift at the surface. Trawls have been more and 

 more improved for sweeping the bottom. Human exploitation of the riches of the sea has 

 little effect on the blue, j)elagic fishes, which are only subject to natural tlurtuations, but the 

 demersal fishes have been seriously affected. Biologists are now jiermanently concerned witli 

 the impoverishment of fishing grounds. The North Sea is becoming dei)ojtulaled, for it is 

 constantly scoured for fishes. As an old English saying has it: "If you drop a shilling into the 

 water near the Dogger Bank, it may not be fished up on the same day but someone is bound 

 to haul it up the day after." 



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