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above is to carry small floating objects in an easterly and 
northerly direction. Thus eggs and embryos floating at 
the surface on the spawning ground to the South-east of 
the Isle of Man will travel easterly with a slight drift to 
the North to Morecambe Bay, the estuary of the Duddon 
and to the Cumberland coast. It is also evident that the 
young fish inhabiting the shallow waters further South, 
that is in the Ribble and in Liverpool Bay and the Che- 
shire coasts, must have originated elsewhere than in the 
spawning grounds referred to. Mr. R. L. Ascroft forms 
us that from his experience of the drift of floating 
wreckage it is probable that fish spawning far South in 
Cardigan Bay and off the Welsh coast generally produce 
the young fish in the southern and central portions of the 
Lancashire coast. Up to the present time the spawning 
areas off the Welsh coast have not been investigated. 
This first pelagic stage of the young Plaice is the 
period during which both embryonic development and 
larval metamorphosis take place. Up to the time when 
the rotation of the eyes is fairly in progress the young fish 
swims freely in the upper layers of the sea, and during 
that change it gradually sinks until, when metamorphosis 
is completed, it finally settles on the bottom. It is gene- 
rally agreed that the young Plaice during this change 
cannot, or at least does not, inhabit the sea at any great 
depth. It is probable therefore that should the larve 
begin to sink while still in deep water their destruction 
follows, and it seems essential that they should have nearly 
completed their larval changes not earlier than the time 
when they arrive at the shallow coastal waters. About 30 
days after hatching the larve seek the bottom and this 
gives a period of over 40 days for them to complete their 
inshore drift from the spawning grounds. 
During this drift inshore the embryos and larve are 
