326 SECTIONAL TRANSACTIONS.—D. 
immediate local concern (i.e. germane to the southern North Sea) there are 
the questions of good and bad survival years for the plaice and for the herring 
of the great East Anglian Autumn Fishery. ‘The latter originate from vast 
annual spawnings in the eastern end of the Channel. It seems that good 
fortune has attended the broods of both fish when, during the egg and/or 
fry stages, the current issuing from Dover Straits has been most average 
in point both of strength and direction. This accords with the supposition 
that good augury for a plaice brood exists when the products of the spawning 
are transported to the continental coastal shallows—the so-called young 
plaice nursery grounds. 
Other problems calling for the application of the Varne light-vessel current 
data in their local role are concerned with the intermingling of two types of 
herring through the straits, and with the outcome of the Belgian Spent 
Herring Fishery. ‘This latter is carried out upon fish supposedly enfeebled 
by the operation of spawning in the eastern Channel. 
Applied at a distance as it were, on the strength of the facts set out above, 
the Dover Straits current data enable something to be said about good and 
poor haddock years. ‘The haddock fluctuates very closely (though oppositely) 
with the herring, and seems, when in the egg and fry stage, to have experi- 
enced the best survival conditions when we should judge the waters to have 
been most strongly urged towards the south. 
The year-class fluctuations of the cod have been studied side by side with 
meteorological data, and it appears that the best augury for a brood obtains 
in those spawning seasons during which winds from the half-compass 
centred on N.E. have been at a maximum—a finding which accords well 
with what was inferred in the case of the haddock from the Varne current 
data. 
Prof. A. C. Harpy. 
Mr. E. R. GUNTHER. 
Two comparisons are chosen to illustrate the importance of vertical 
currents to biology. ‘The first between the Labrador Current, which flows 
over the rich fishing-grounds of the Newfoundland Banks, and the Falkland 
Current, which flows over the less rich grounds of the Patagonian Shelf. 
These two are analogous currents, since they are both regarded as compen- 
sating for the eastward deflections of the Gulf Stream and of the Brazil 
Current. But they are not homologous, since the Labrador Current has an 
arctic origin and is consequently rich in nutrient salts which are brought to 
the surface through the agency of vertical currents induced by melting ice ; 
and the Falkland Current, having its origin in the water of the West Wind 
Drift, is not of antarctic origin and consequently is less rich in nutrient 
salts. 
The second comparison is between the oceanography of the Patagonian 
Shelf on the East Coast of South America and that of the Humboldt or 
Peru Current on the West Coast. Conditions on the Patagonian Shelf are 
such that the Falkland Current converges with the coast and the water 
circulates in a more or less closed system, and consequently there is a limited 
tendency towards upwelling. On the West Coast, on the other hand, the 
work of the Royal Research Ship William Scoresby has demonstrated the 
presence of a divergence line along the coast whereby upwelling of cool water 
rich in nutrient salts from the lower layers is induced: To this is attributed 
the outstanding richness in the marine fauna for which the West Coast is 
notorious. 
