42 Part L11.—Twenty-jirst Annual Report 
off from it by The Gut, and is more distant. The Fisher Bank plaice 
must at all events travel a long distance from the beaches in the course 
of their growth. 
That plaice do travel great distances has been shown by the experi- 
ments I made some years ago by marking large numbers in the Firth of 
Forth and neighbourhood. It was found that they migrated northwards 
along the coast, and some which had been liberated in the Firth of Forth 
were caught a year and more afterwards in the Moray Firth, more than 
150 miles from the place where they were set free. Still later, another 
was re-taken near Dunnet Head, on the north coast of Caithness, near 
the Orkney Islands, which must have travelled at least over 200 miles 
from the place of liberation. In all these cases the movement of the 
plaice was in a direction opposite to the prevailing surface current.* 
From observations I have made on the rate of movement of the plaice 
confined in the large tidal-tank at the Bay of Nigg Laboratory, some 
idea may be gained of the distance that might be covered in a short 
period. The piaice there are tame and swim leisurely around the tank 
near the surface, especially at feeding time, and I found that while 
gently swimming in this way they moved at the rate of from 100 to 140 
feet ina minute. This leisurely movement, if continued for one hour, 
would take them a distance considerably over a mile; when disturbed, 
as by pushing a stick into the water, they dart off with great rapidity. 
Since the smallest plaice taken on the deep-water grounds was some 
years of age, it is easy to understand how a distance of 50 or 100 miles 
can be traversed by them by a leisurely movement, even if it were 
accomplished at long intervals. 
FLOUNDER (Pleuronectes flesus). 
In the hauls on the trawlers comparatively few flounders were taken, 
and they were for the most part large, although not always taken to 
market. From the known habitat of this fish—more shore-loving and 
estuarine than the plaice in its early stages, and never wandering into 
deep water when adult—this was to be expected, and the observations 
made are chiefly of interest in connection with its migrations from the 
shallows into moderately deep water. 
The facts establish two well-marked migrations of the flounder from 
the shallow water to the deeper water, onein early spring and the other 
in autumn. ‘The statistics of the “‘ Garland” may be first summarised. 
At the seven stations in the Firth of Forth, in 575 hauls of the net 
throughout the year for ten years 1886-1895, the 321 flounders taken 
were thus distributed in the different months ; the Table also shows the 
distribution of the flounders taken in St. Andrews Bay in the same 
period, and in the Moray Firth by the “ Garland” in the years from 
1886 to 1900 :— 
* Eleventh Ann. Rep., Part I11., p. 186. Fifteenth ibid., p. 374. 
| TABLE. 
