176 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



in the shrimp trawl. If the number of fish caught in 

 any one haul be divided by the numbers of quarts of 

 shrimps taken at the same time, a measure is obtained of 

 the amount of destruction of young fishes caused by 

 shrimp trawling. Taking the total monthly catches of 

 shrimps and fish during the year, as shown in Tables III. 

 and TV., as a basis, we have constructed Table Y. That 

 table shows for each month in the year, and for both 

 areas, how many soles, plaice and whiting were caught 

 for every quart of shrimps. And if it be possible to 

 determine by any means the total number of quarts of 

 shrimps landed from the Mersey Shrimping Grounds in 

 each month during the year, the numbers on this table 

 will serve as factors which will enable the amount of 

 destruction of immature food fishes to be calculated* 



The numbers of plaice caught per quart of shrimps on 

 Area B during February and March seem excessive. This 

 is due first to the relatively large numbers of plaice found 

 on that ground during the early months of the year ; 

 second, to the very small catches of shrimps made there 

 during those months. 



The tables show that the numbers of soles, plaice and 

 whiting caught per quart of shrimps on Area A is always 

 much greater during the third quarter of the year than 

 on Area B during the same period. More exactly, more 

 whiting are caught on Area A from June to December, 

 and more plaice and soles from August to October, than 

 on Area B during those same months. More whiting 

 were caught on Area B than on A during February, and 

 more soles during March, May, Tune, July, November 

 and December. 



We have used the term destruction as synonymous with 

 capture of young fish, but perhaps we are not strictly 

 justified in doing so. All the fish brought up in a shrimp 



