324 THE SEAS 



for by means of the "grab" mentioned on page 263, but 

 here again the chances are small of the instrument picking 

 up a sample of the bottom from exactly the right spot. 



Let us now trace the life story of the plaice in the southern 

 North Sea. Research carried out on the lines indicated 

 above shows that the mature plaice gather into a region 

 some little way off the Dutch coast : here the eggs are 

 discharged and drift freely in the water for about a fort- 

 night, at the end of which time they have been carried by 

 currents further north and considerably nearer the coast. 

 From the eggs hatch those little symmetrical larvae 

 mentioned in a previous chapter (Plate 112). The movements 

 of the plaice can be followed by making catches with a very 

 large coarse-meshed tow-net. It will be found that by the 

 time they are about three-quarters of an inch in length they 

 are being drifted very near to the coast. When they have 

 reached this size they suddenly disappear from the tow- 

 net catches. Their metamorphosis has taken place, that 

 is the left eye has moved over to the right side of the head 

 and the fish has assumed the typical adult characters. 

 At this stage the fish seeks the bottom. It must then be 

 sought with the aid of a fine-meshed trawl, such as the 

 shrimp-trawl. A search will reveal that the young plaice 

 have moved into the shallow water covering the sandy 

 flats that occur all along the Dutch coast. Here fish between 

 one and two inches in length can be caught in immense 

 numbers. When the plaice are of this age they can often 

 be found in the sandy pools left uncovered by the tide. 

 As an illustration of this a photograph is given in Plate 

 115 of such a pool in the Gannel Estuary at Newquay, 

 Cornwall. Two of us fishing in this small pool for just under 

 an hour with small prawning nets early in June captured 

 the forty young plaice shown in their natural size on 

 Plate 116. There were probably still many left in the pool 



