238 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
caught on the ‘‘ Liverpool Bay’’ fishing grounds; and 
(3) plaice caught on the ‘‘ Bahama Bank” area. In 
addition, three fishes have been recaught outside the 
Irish Sea. The lengths of the fishes caught in these 
three groups differ significantly. (1) Those taken in the 
Bay and along the coast have a modal length of 23 
centimetres: they have been taken inside the _five- 
fathom line; (2) the mean length of the plaice 
Le) 
caught on the ‘‘ Liverpool Bay’”’ fishing grounds is 
26:5 cms.: they were mostly taken between the 10 and 
20-fathom lines; (8) the mean length of the fish taken on 
the ‘‘ Bahama Bank ”’ area is 29 cms.: they were caught 
just outside the 10-fathom line. Thus there is a 
progressive increase in mean length of the fish taken in 
order of the three areas. 
The season of recapture also varies progressively : 
(1) The fish recaptured in Morecambe Bay and along 
the coast. line were taken almost all in April-May; 
(2) those recaught in the “‘ Liverpool Bay’’ area were 
caught during the months June to September; and 
(3) those recaught on the Bahama Bank area were mostly 
caught during the months October to March. 
These facts can be put together to form a fairly 
probable picture of the movements of plaice with respect 
to the Morecambe Bay area. The small plaice caught 
there are those that inhabit the in-shore waters in their 
earlier stages. They originate from the eggs and larve 
drifted in from the off-shore spawning areas, and the fish 
remain on the shallow water grounds until they reach a 
length of about 20 cms. Migration then begins, and 
plaice measuring about 20 to 27 cms. shoal on the 
feeding grounds just off the land in the spring of the 
year. About the middle of the year fairly large catches 
of plaice, a little larger than those just mentioned, may 
