SEA-FISHERIES LABORATORY. 101 



Further, the composition of the shoals reaching shallow 

 water off the Welsh Coasts appears to vary with the locality. 

 The fish do not show the same range of length, and this 

 indicates that the shoals are of different ages. But far too 

 little investigation has been made to show up this difference 

 verv clearlv. 



Life-History of the Plaice in Lancashire and Welsh 



Waters. 



A considerable volume of data has now been accumulated 

 with regard to this subject, and advantage has been taken of 

 the necessary cessation of the investigations to summarise 

 these results. They are now in manuscript form and will be 

 published when it is appropriate. 



Size of Plaice in Local Waters. 



About 134,000 fish have been individually measured on 

 board the Committee's vessels immediately after capture. 

 The localities of capture and all other associated information 

 are known. 



Tables have been prepared showing the range of sizes 

 of the plaice captured and measured on each important fishing- 

 ground, and at each month during the various periods of 

 the fisheries. 



These data have beeu reduced statistically, so that the 

 degree of probability of the conclusions derivable from them 

 can be reckoned. This has involved a considerable degree of 

 arithmetical work, but such is necessary if the results are to 

 be employed in framing regulations. Crude data of observation, 

 by themselves, are of little statistical value. 



Theoretical frequency curves, and "tables of dispersion" 

 based on the above measurements have been prepared. 



