214 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



in the case of the winter fishery, and a higher size-limit 

 would be demanded. This would now differentiate against 

 the smacks, and in favour of the steam trawlers who would 

 (supposing that the argument is sound) fish for these plaice 

 after they had migrated from out the Beaurnaris-Red 

 Wharf area into the deeper waters to the mouth of St. 

 George's Channel.* 



(7) The Length-Weight Coefficient k. 



This has been determined in the case of all samples 



of plaice received at the laboratory. The fish were sorted 



and weighed, and then the average weights on the 1 cm. 



groups were calculated, and from these series the 



f k 

 coefficient h in the expression / hPdl was evaluated as 



described in previous reports. 



By using tables of the fourth powers of the numbers 

 15'5 to 35'5 (the commonly occurring mean lengths), and 

 of the logarithms of the powers of these numbers, the 

 calculations of h were rapidly and accurately made. The 

 results are given in Table XV (for the year 1913) and XXV 

 (for the years 1909-1913). 



It is doubtful whether (so far at least) these results 

 have any useful or even theoretical application. If the 

 series of samples examined during the years 1909-1913 

 had been more numerous, had, in fact, been really repre- 

 sentative of the fisheries studied, then something might 

 have been deduced from the tables of ^-values. As it is 

 the series are too incomplete to be of much use. 



Anyhow the results are summarised in Table XXV, 

 and I give here a graph of the mean values of Jc for the 

 whole district investigated, and for all the years 1909- 

 1913. The curve is drawn smoothly through a series of 



*This question is further discussed in the introduction to the Report on 

 the plaice-marking experiments in the present Report. 



