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much greater. Probably about 9 inches will represent the 
average size of the fish caught in Morecambe Bay and 
generally within the 3 miles limit. These fishes are now * 
marketable, and in suitable places all along the coast great 
quantities at this size are caught in the stake nets. Larger 
individuals are of course often got, but on these in-shore 
fishing grounds mature Plaice are never or only very 
exceptionally captured. It is these immature fishes which 
in their gradual migration outwards form the mature 
Plaice population of the more open sea. At or near the 
Spawning season they congregate on the spawning 
grounds. 
Briefly summarized then the migratory movements of 
the Plaice are (1) the passive drift in-shore of the develop- 
ing eggs and metamorphosing larve terminating as the 
larva acquires the adult form and settles to the bottom, 
and (2) the slow outward movement of the young fish, 
deeper water being continually sought as it increases in 
size. This movement ends as the fish becomes mature. 
Thereafter its movements are probably very limited. 
During the spawning season it probably does not travel at 
all. With the extrusion of spawn another generation 
begins the migratory cycle.* 
* We have described only the larger migrations which are part of the 
life movements of the Plaice. Smaller and local migratory movements 
are of course continually going on. Mr. R. L. Ascroft informs us of a 
curious instance which illustrates the connection between these smaller 
movements and physical events. A severe storm about 1885 was followed 
by a very marked increase in the numbers of Plaice in one of the channels 
of the Ribble estuary—the Bog Hole. For about four days great 
quantities were caught, one of the sailing trawlers getting as much as 
180 score of fish (value £30) in a day. ‘The cause of this remarkable 
abundance was’ that the storm and rough water washed off the ‘Sand 
pipes”’ (Pectinaria belgica), which existed in great abundance on the 
neighbouring banks, into the channel, and the Plaice followed the food. 
