of the Fishery Board for Scotland. 
259 
hatched in the most suitable conditions. There is reason to believe that 
in some cases {e.g. plaice), the spawning process may be delayed until the 
set of the currents is suitable for the transport of the fertilised ova shore- 
wards. We know most perhaps about the spawning and spawning grounds 
of the plaice. In January and February great shoals of very large ripe 
fish, the males averaging about sixteen or seventeen inches in length and 
the females about twenty-four inches, congregate on grounds at distances 
from about eight or ten to twenty miles from the East Coast. In the 
neighbourhood of the Forth and St Andrews Bay these shoals are mainly 
found above eight or ten miles off ; off Montrose they may occur up to 
twenty-five miles. A great spawning ground is Smith Bank in the Moray 
Firth. This bank lies in from 18 to 20 fathoms of water, sixteen miles 
from the west side of the Moray Firth, and about thirty miles from the 
south shore. The bottom is hard, and the invertebrate fauna not abundant. 
Comparatively few fishes are obtained on this ground except at spawning 
time; and very few young fishes. It is therefore a typical spawning 
ground, to only a slight extent a feeding ground, and in no sense a 
nursery. Successive shoals of plaice, cod, and haddock frequent it for 
spawning purposes. Ripe plaice congregate on Smith Bank in large 
numbers in January or the beginning of February. They come to 
some extent from the inshore waters; but mainly from offshore. It 
is not possible to state from what distance offshore they may come, 
but some of them probably travel considerable distances, for large 
spent fish were obtained at the end of May at the 'Garland' Stations 
at the mouth of the Dornoch Firth, nearly thirty miles from Smith 
Bank, which had probably come from that ground or its vicinity. The 
plaice continue spawning during February and part of March, and then 
disperse. The fertilised ova are obtained in great numbers over the 
spawning shoals and in the waters between Smith Bank and the shore, 
towards which they are gradually drifted. Scarcely a single immature 
plaice, and none of small size, was obtained by the ' Garland ' in its 
many trawlings over this bank and its neighbourhood ; while abundance 
of immature individuals are obtained inshore, and the smaller the nearer 
to the beach. As they increase in size they gradually migrate to deeper 
water. During the time when plaice are spawning at Smith Bank the 
general direction of the wind and therefore of the surface currents is 
north and east and will tend to carry the floating and developing ova 
shorewards. Similarly, in spring the winds on the East Coast of Scotland 
are generally easterly ; and hence the ova thrown from spawning shoals 
ten or fifteen miles off are gradually carried during their development 
towards the shore. There is little evidence as to the phenomena of the 
spawning of fish on the West Coast ; but many of them spawn much 
nearer shore than on the East Coast. 
Among most or all fishes which frequent the territorial zone, but go 
offshore to spawn, many fully adult, but not ripe individuals remain in 
the territorial waters throughout the spawning time. This is the case 
with haddock, cod, whiting, plaice, &c. Some of those in this condition, 
at the beginning of the spawning season, no doubt ripen and spawn before 
the season closes ; but large numbers certainly do not. Another point of 
interest is the mixture of mature and ill-developed adults, which some- 
times occurs on the same ground. For instance, among long rough dabs, in 
one haul of the net individuals of all sizes from six to twelve inches may 
be found with the reproductive organs fully developed and ripe, or scarcely 
developed at all. It is possible that in such cases the adults do not 
spawn every year. 
A summary of the chief results obtained is given below. 
