230 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



sizes, from 2\ to 22 inches, are present on the same 

 ground. Large plaice are present on the Luce Bay area 

 because they are not caught, and, conversely, they may be 

 absent from the Lancashire nurseries because they are 

 fished out, and not because the latter areas are naturally 

 small fish grounds. It is, of course, quite proper to use 

 the term nursery in relation to the latter areas, but it is, 

 most probably, the artificial conditions resulting from 

 commercial trawl fishing that have called into existence 

 the apparent segregation of small immature fishes on these 

 in-shore grounds. 



The results of hauls 1 and 2, on 19th October, are 

 incidentally of interest in connection with the question 

 of how far a haul with a trawl net is to be regarded as 

 affording a fair sample of the fishes present on the area 

 swept by the trawl net. At the suggestion of Captain 

 Wignall, these hauls were made over the same strip of 

 ground (as determined by shore marks), but in opposite 

 directions. The catches are given below in parallel 

 columns : — 



Fish caught. 



Haul 1. 



Haul 2. 



Plaice over 14" long 



Plaice under 14" long 



Dabs 



7 

 74 



25 

 8 



12 



81 

 21 



Raia clavata 



6 







Total food Fishes caught... 



114 



120 



The similarity of results between the two catches is 

 very striking, especially when it is remembered that it 

 *s very difficult to trawl over exactly the same strip of sea 

 bottom, and, further, when the marked differences which 



