SEA-FISHERIES LABORATORY. 105 



or 60 millions of young cod adds to the stock in that fjord, 

 tKe benefit may be great even if from other causes the 

 average per haul in the following year shows a decrease. 

 An addition has been made to the natural stock of fry — 

 whatever that is — and that may well have a beneficial effect 

 upon the future population whatever, as the results of 

 various factors, that may come to be. 



Plankton Investigations. 



During the past year a larger number of plankton 

 gatherings have been obtained by tow-nets than ever 

 before, and these have been very carefully examined by 

 Mr. Andrew Scott. Four hundred gatherings in one year 

 from a limited area like the Irish Sea ought to give useful 

 information, and the value of the series is increased by 

 the fact that in so many cases we have gatherings taken 

 from different parts of the area on the same day, 

 amounting to practically simultaneous observations. The 

 advantage of having several centres of work in the district 

 — the steamer, the bailiffs, Piel and Port Erin— from which 

 observations can be taken is obvious in an enquiry like 

 this; and Mr. Scott's lists and tables given below will be 

 seen to be an interesting contribution to a subject that is 

 still imperfectly known. Before any far-reaching con- 

 clusions can be drawn from plankton gatherings it is clear 

 that we must be sure what it is that our nets are catching, 

 and how far the samples caught on different days or at 

 different localities or with different nets are comparable, 

 and can be said to be representative of any time or place. 

 With a view of testing such points I chartered a small 

 steamer for two months last summer and took almost daily 

 gatherings, with several different kinds of tow-nets, 

 during August and September. In all, about 80 samples 

 were collected in 40 days, and the main result is to show a 



