258 
Part III. — Eighth Annual Report 
been got as early as" January and as late as August. It spawns chiefly in 
June. 
2. Spawning Places. 
; It is well known that many sea-fish resort year after year to the same 
grounds for spawning purposes. In the case of the herring, which 
deposits its eggs on the bottom, the spawning grounds are generally 
within or close to the territorial waters. The spawning places of nearly 
all sea-fishes whose eggs are pelagic, lie, however, at distances more or 
less remote from shore, and beyond the territorial waters. In the case of 
some small flat-fish, such as the common dab, the flounder, and to a less 
extent, the long rough dab, spawning goes on as well within as without 
the territorial waters ; these fish appear to spawn almost wherever they 
happen to be, and the adults are present in relatively large numbers near 
the shore. Among round-fishes, the gurnard also spawns to some extent 
within the territorial limit, but to a greater extent beyond it. None of 
these fishes appear to congregate in well-defined shoals. The gurnard is 
rare near the shores in winter. They begin to approach the coast, 
apparently to spawn, in March and April, and leave in October and 
November. With the above exceptions, all the food-fishes spawn offshore ; 
notably those which congregate in great shoals at the spawning time, such 
as cod, haddock, whiting, plaice, mackerel, &c. Why should great shoals 
of cod, haddock, whiting and plaice, congregate at distances of from about 
eight or ten to twenty miles from shore, on the East Coast, for the 
purpose of propagation? There is evidence that shortly before the 
spawning period, large, fully adult and nearly ripe individuals are found 
within two or three miles from shore ; that no fully ripe specimens are got 
near shore during the time of spawning ; and that after the spawning is 
over large spent fish are caught in the territorial waters. The nature of 
the bottom does not seem to have much influence ; as a rule it is sandy or 
hard, but such bottoms are as common inshore as offshore. I think 
the selection of offshore sites for spawning may be explained by the 
following considerations :^(1) The conditions which regulate the choice 
of the spawning place have reference specially to the welfare of the 
progeny; (2) the grounds close inshore afford the maximum of food, 
shelter and warmth for the rearing of the newly hatched young ; and in 
these areas very young fishes abound ; (3) the eggs are pelagic and are 
hatched at or near the surface, generally within a week or two after 
fertilisation, during which time the great majority are carried by the 
prevailing surface currents towards the shore, so that the larval fishes find 
themselves in the best conditions for their security and growth. The 
pelagic ova of cod, haddock, whiting, plaice, &c. have been obtained in 
large numbers close inshore, where no spawning fish occur, and many of 
these have hatched out within a day or two after they were taken. If 
these fish whose ova float were to spawn, like the herring, close to the shore, 
a large proportion of the eggs would be stranded on the beach, or carried 
into turbid or brackish water, and destroyed. I believe it will be found 
that the selection of spawning grounds is determined chiefly by the 
physical conditions, in relation to the transport of the developing ova to 
the places where the young are reared. A considerable proportion of the 
pelagic ova spawned at the offshore grounds are no doubt carried seawards 
by the surface currents produced by winds blowing offshore, and the larval 
fishes in many cases find themselves in conditions less suitable for their 
growth and safety. This is probably one of the main reasons tor tne muca 
greater fertility of the fish which produce pelagic eggs than those whose 
eggs are demersal. In the latter case the eggs are fixed and the young are 
