SEA-FISHERIES LABORATORY. 285 



influenced, to a minimum. Table IX shows the mean 

 temperatures for the four sample months, February, 

 May, August, and November, at a number of stations, 

 coastal and off-shore ones. The means have been 

 calculated for the four years 1909-1912 only, since these 

 are the only years for which temperature records for the 

 coastal stations are available. It will be seen that there 

 is an area of sea extending from about Morecambe Bay 

 to the Mersey Estuary— bounded roughly by the parallels 

 of latitude 54° 00' N. and 53° 30' N., and by the 

 meridians 3° 00' W. and 3° 30' W.— where the annual 

 temperature range is relatively great; and where the 

 minima are low and the maxima high. Thus at the 

 Stations, Morecambe Bay and Liverpool North-West 

 Light Vessels, at Nelson Buoy, and at Liverpool Bar the 

 range varies from about 10° C. to 12'5° C, the minima 

 from about 4° to 6°, and the maxima from about 155° 

 to about 16"5 . This part of the sea is influenced by the 

 strong tidal streams which oscillate between the sand- 

 banks in the bays and estuaries, and the open sea off- 

 shore. The great extent of sand laid bare by the ebb- 

 tide cools the water flowing over it in the winter months, 

 and warms it to a corresponding extent in the summer. 

 This area includes most of the summer fishing grounds 

 for soles and plaice. 



The mean temperatures for the two principal series 

 of hydrographic stations are also given in the Table. 

 Stations 1 to 4 lie along the 54th parallel of latitude, 

 Station 1 being about 10 miles from the land, and it and 

 the others are 10 miles apart. The temperatures at these 

 stations do not differ very much in the months 

 May and November, but in February, the month of the 

 minimum, the temperature falls as we pass out from the 

 land, while in August, the month of the maximum, the 



