2700 
spot where hauls were made, from the coast of Holland up to the Skaw. On the Eng- 
lish and Scottish coasts, the 40 metre line runs for the most part so close in to land that 
I was unable to make any hauls there, except in the Firth of Forth, (permission being 
courteously granted me by the Scottish Fishery Board). In autumn, group I is encoun- 
tered farther out from land, and at greater depths; it then includes also considerably 
larger fish. 
Group II was hardly ever taken nearer to land than the 40 metre line; its area thus 
appears to be between the 40 and 80 metre limits, or on the edge of the 80—100 metre 
depth. 
It would hardly be justifiable to attach any superlative importance to these attempts 
at determining the occurrence of the groups, at any rate, as a general and permanent 
solution of the problem of the distribution of young herring in the North Sea. It should 
however, be permissible to conclude from these investigations that the younger stages 
of the herring, like the corresponding stages of many other important fish, are chiefly 
to be found at lesser depths; 1. e. in the shallower waters of the Banks, and more or less 
close to land. This was also the point which I regarded as of primary importance. 
Comparison of the distribution of the youngest year classes with the cur- 
rents in the North Sea. 
In considering the herring of the Norwegian coastal waters, we have seen that the 
young fish are carried by the current far away from the spawning grounds, and spread 
in the direction of the current northwards along the coast. It would seem reasonable 
to suppose that somewhat similar conditions prevail in the North Sea. Judging from 
the available information as to the currents of this water, it would seem that a strong 
current sets southward from the north coast of Scotland and the Shetland Isles, towards 
the Dogger Bank and the German Bight, and thence again through the Skagerak towards 
the coasts of Sweden and Norway. The well known and excellent experiments with 
drift bottles carried out by Dr. Fulton give a very good illustration of this, (see Fig. 35) 
and would appear to agree directly with the results given above as to the occurrence 
of the younger stages of herring. In consideration of the question, it should, however, 
always be borne in mind that quantities of young herring occur along the whole range 
of the east coasts of England and Scotland, and that the waters to the north and north- 
west of Scotland are also particularly rich in young herring of different sizes. Fishery 
is even carried on here in the spring, for the young fat herring (matjes). 
Taking all this into consideration, it would appear desirable that also the younger 
stages be made the subject of investigation as regards their race and growth, in the 
same manner as the spawning shoals. For a comprehension of the geographical areas 
of distribution of the different races it is naturally of particular importance to ascertain 
whether the young herring encountered along the coast include the young of both coast 
and ocean forms, whether the young stages of Shetland herring also grow up in the southern 
waters of the North Sea, or only near the coasts of Scotland and the Shetland Isles. In- 
numerable interesting results will doubtless be arrived at on these points in course of 
time; for the present, we must in all probability suppose that roughly speaking, the 
southern part of the. North Sea is one of the largest and.most important growth centres 
