37G 
MR. T. SOUTHWELL ON THE HERRING FISHERY. 
facts. Mr. Matthews states that undoubtedly the samples of fish 
submitted to him represent the size of the fish caught ; 
but he finds it necessary to consider how far they represent the 
actual size and condition of the fish frecpienting the Scottish coast, 
for, says he, “it has to bo noted that tlie size of the fish sent to 
me for investigation or, to speak more generally, of all the fish 
brought ashore, is rather an evidence of the size of the mesh of 
the nets employed for their capture than a criterion of the actual 
size of the Herring in the sea ; and according to the size of mesh 
we shall be liable to misjudge the actual size of the fisli. 1 feel 
sure that the want of sufficient consideration of this fact, and 
especially of the circumstance that change of size of mesh has 
occurred, for any period or at any place, has given rise to 
erroneous ideas as to the preservation or decline of the general 
or natural size of the Herring ; for, of course, it must be 
remembered that a particular size of mesh only takes those fish ; 
which fit it, that is to say, does not merely allow the smaller fish 
to escape by passing through its meshes wliile sweeping in all the ^ 
larger, as in Salmon net or Seine trawl, but the large fish also, | 
to a great extent, escape by not getting their heads into the mesh.” 
He also mentions that some of the largest fish he received, 
averaging twelve inches long, were “scummed fish,” that is, fish 
which having been insufficiently meshed drop out of the net, but 
are “ scummed ” up from the surface by a boy appointed for that 
purpose ; and expresses an opinion that it is almost certain the 
largest fish seldom become properly meshed. As a practical jiroof 
of the accuracy of these observations, Mr. INIatthews gives the 
measurements of two samples of Herrings taken at the same time 
and place, one by a net, the meshes of which were considerably 
shrunk from being re-barked seven or eight times, and the other 
by a net which had been little used, and was therefore considerably 
wider in the mesh. In the former instance the fish averaged 
268'6 m.m. (10| in.), and in the latter 284 m.m. (llfV)> clearly 
showing the relation between the size of the mesh and that of tlio 
fish taken by each net. The experience on the Scottish coast is 
that although sexually mature fish may differ greatly in size, which 
difference may possibly be racial, still “ of the fish caught in the 
early part of tlie season, a much larger proportion arc immature 
and small, and probably also younger tlian is tlie case later on. 
