78 
BULLETIN OF THE BUREAU OF FISHERIES 
certainly one of the most important off the American coast, may even contribute 
to the fish stock of the Grand Banks. 
Haddock or any other bouyant eggs spawned on Browns Bank, or German 
Bank to the north of it, would probably tend either northward into the gulf or west- 
ward toward Georges Bank, depending upon the precise state of the Nova Scotian 
current at the time; and it is probable that this was the source of the cod-haddock 
eggs towed over the eastern side of the basin on May 6, 1915 (station 10270), and 
on April 17, 1920 (station 20112). Larvee hatched on Browns and German Banks 
might be expected to follow the same route during the spring, if living at about 40 
to 50 meters, which it is probable that most of them do. Eggs spawned on Browns 
and German Banks after the rush of water past Cape Sable has slackened, would 
be more apt to be drifted northward toward the Bay of Fundy, but this would apply 
mostly after the spawning season of the haddock had passed. 
It is obvious that if practically no production of the species of gadoids and 
flatfishes that lay buoyant eggs takes place in the Bay of Fundy, and if most of those 
produced along the northern side of the gulf drift away to the southwestward, as 
the evidence marshalled above seems to prove, there must be as regular an immigra- 
tion of the older fry back again to maintain the stocks of adult fish. However, this 
subject does not immediately concern the plankton. 
It is interesting to compare the chart of gadoid and flatfish fry (fig. 35) with 
the corresponding chart for the rosefish (Sebastes), a viviparous species (Bigelow 
and Welsh, 1925, fig. 120), as an illustration of the degree to which the dispersal 
of larval fishes depends on the precise locality where they are produced. In the case 
of the former this happens chiefly inside the 100-meter contour, with the result just 
described. No doubt, when young rosefish are born in that belt and chance to rise 
near the surface they follow the same route, journeying with the dominant set. But 
rosefish also produce their young general^ over at least the northern half of the 
deep basin of the gulf, where the dominant anticlockwise eddy is felt less. It is 
also probable that in most cases the young Sebastes, like their parents, live 
rather below the level of the most active currents, hence are less apt to be caught 
up by them. Further (though less important in its effect than is the location of the 
breeding grounds in relation to the circulation of the gulf) , Sebastes is so compara- 
tively large and strong at birth that its involuntary migrations cover a shorter period 
than those of most of the fishes that lay floating eggs, and consequently its larvae 
are to be found widespread, except close to land, and not concentrated in any one 
part of the gulf. 
QUANTITATIVE DISTRIBUTION OF THE ZOOPLANKTON 
To give an adequate quantitative picture of the plankton would require a far 
greater number of vertical hauls than have yet been made in the Gulf of Maine. Not 
only are the seasonal gaps in the series serious, but hauls should be located closer 
together than has been feasible for us, even in July and August, unless the plankton is 
more uniform than our work suggests. However, even a cursory examination of the 
zooplankton, if extended over a considerable area or through a considerable period of 
time, is certain to reveal wide fluctuations in abundance as well as in its qualitative 
