288 
North Sea Investigations. 
By 
Ernest W. L. Holt. 
On THE Destruction or ImmMarurE FisH 1n THE NortH SEA. 
I supsorn the results of statistical imquiries into this question, 
continued from the point at which they were left in the last number 
of this Journal. Having been permitted by the Council of the 
Association to undertake a series of lectures along the coast of 
Yorkshire on behalf of the North-eastern Sea Fisheries Committee 
during the present autumn and winter, I find it necessary to restrict 
the present paper to the smallest possible compass, reserving practi- 
cally everything except the mere statement of figures until more 
time shall be available for the deduction of results. 
I regret to have to say that the statistics for the month of May 
are by no means complete. Bibliographical work in connection with 
several scientific papers on which I was then engaged necessitated 
my absence from Grimsby during the early part of the month, and 
the sudden illness of my subordinate during the same period inter- 
fered with the arrangements I had made for keeping up the records. 
The statistics as to plaice are, therefore, a blank for the first week of 
May ; Mr. Clark unfortunately remained unwell for the rest of the 
month, while a serious break-down in the circulating apparatus of 
the Cleethorpes aquarium made great demands upon the time which 
I should otherwise have been able to devote to market observations ; 
and, though I was able to keep account of all plaice landed, my 
statistics as to haddock and cod are too meagre to be worth insertion. 
The gas-engine for water circulation was finally restored to good 
working order, but, to guard against any future temporary 
break-down, I have fitted the entire series of sea-water tanks with 
an apparatus for air circulation, on a pattern communicated to me by 
Dr. G. H. Fowler. 
It has proved that this air circulation is quite sufficient to keep 
the tanks properly aérated throughout the night, and we have thus 
been able to save the excessive labour and expense (for gas) which 
the smallness of our reservoir had hitherto entailed in pumping by 
night as well as by day. 
