NORTH SEA INVESTIGATIONS. 23 



212 was under Sin. Of the sample from the home grounds, there were 

 no males under 10 in., no females under 11 in. Of fish from the Dogger 

 Bank and grounds to the south of it, the lower limit was 9 in. for males 

 and 10 in. for females. In the first sample from the Sylt ground, the 

 minimum was 7 in., and there was only one fish out of 55 under Sin. 

 In the second sample, selected from 4 boxes, the minimum was 6 in., 

 and there were 104 fish out of 187 under Sin. At Billingsgate, a 

 considerable numbe'r of the plaice landed were under 6 in. The upper 

 limit is also of some importance, although it is not fully determined by 

 these observations. Of the fish from the Sylt ground none were above 

 13 in. in length ; in the sample from the Leman ground the upper 

 limit was 14 in., but there were plenty larger than this in the same 

 catch, and in all the other samples there were fish over 14 in. 



It appears, therefore, that in the period covered by these observations, 

 the usual minimum on the off-shore grounds is 9 in. for males, 10 in. 

 for females, but occasionally it may be as low as 7 in, and 9 in. Fish 

 below these limits have been obtained only from the Sylt ground and 

 the Humber. Parts of the Dogger Bank are quite as shallow as the 

 Sylt ground, where the small plaice are taken, yet such fish are not found 

 there. Proximity to the land, therefore, appears to be an essential condition 

 in the rearing of young plaice. But the question is, why are the small 

 plaice so much more abundant on the Continental than on the English 

 side ? There can be no doubt that the history of the plaice is the same 

 on the two sides. We have sufficient evidence that the plaice hatched 

 from January to March, are to be found abundantly, in summer, along the 

 edge of the shore on the English side, wherever there is sand or sandy 

 mud. Those of a year old, and some of those which are two years old, 

 are the small plaice which are taken to market by the inshore boats in 

 the Humber, and all along the coast of Lincolnshire, Norfolk, Suffolk, 

 and Essex, and by the large trawlers from the Eastern Grounds. But 

 the difference in numbers obtained on the two sides is enormous. On 

 the eastern side a steam trawler brings in between 200 and 300 boxes 

 after about a fortnight's fishing, but I have not heard of a large trawler 

 ever having been able to get a voyage of small plaice on the English 

 side. The cause of the difference seems to me to lie in the confifaira- 

 tion of the sea bottom. There is a rather broad tract, less tlian 20 

 fathoms deep, extending from England to Holland, from the latitude 

 of the Humber to that of the north coast of Norfolk. But north of 

 this region the 20 fathom line is about 40 miles from the coast of the 

 islands on the Continental side, from 15 to 3 miles on the Englisli side. 

 South of this region also there is a depression deeper than 20 fathoms, 

 which is nearer to the English side tlian to the Continental. It may be 

 true that more of the fioating eggs and larva) of plaice are carried to 



