172 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



The shrimp-fishery in the Mersey Channels proceeds 

 throughout the whole year, and small plaice are nearly 

 always taken here in considerable numbers. All the 

 months of the year are represented, but the data for the 

 summer and autumn months are not so numerous as they 

 ought to be. This is a defect that ought to be made good, 

 for these statistical results are of considerable interest : 

 from them we ought to be able to trace the growth and 

 migrations of both soles and plaice during the first two 

 years of life. Similar data ought to be obtained from the 

 Blackpool Closed Ground and the shrimping . grounds in 

 Morecambe Bay. Great as is the interest and importance 

 of these fisheries, they have hardly been investigated in a 

 really adequate manner. Finally, the plaice fishery off 

 Great Orme's Head, in Conway, Beaumaris, and Red 

 Wharf Bays is an autumn and winter one. It has a rather 

 sharply-marked period, beginning sometimes in the 

 autumn, and culminating in November to January, 

 according to the season. I have already* referred to this 

 fishery : it is one that ought to be very closely studied, for 

 all the data for a complete study of fishery seasons and 

 productivity in relation to hydrographic conditions ought 

 to be obtained by the investigation of this area, and by 

 a rigorously accurate collection of the statistics of fish 

 landed from these grounds. So far as the data available 

 go, they only suggest such relationships; but far more 

 exhaustive material is required before the latter can be 

 demonstrated in detail. 



In the Summary Tables XVI to XXI the actual 

 length-frequencies are given : these have been obtained by 

 adding together the numbers of plaice taken in each 

 centimetre group for the corresponding months of the 

 five years. In addition to this, the frequencies are also 

 *Ann. Kept. Lancashire Sea Fish. Laby. for 1912, pp. 133, et seq. 



