72 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



ship has entered the Labrador current. The catch of plankton 

 is suddenly increased enormously, and consists of an entirely 

 different assemblage of organisms ; and this abundant plankton 

 is probably definitely related to the great fisheries on the 

 Newfoundland Banks. 



Observations in the Irish Sea and on the West of Scotland 

 have shown that the plankton at a locality may fluctuate, both 

 in amount and essential nature, from year to year ; and 

 although a definite relation between these fluctuations and the 

 variations in the distribution and catches of fish has not yet 

 been established, it is reasonably probable that a fuller and 

 more detailed knowledge of both will enable a correlation to be 

 demonstrated. 



It is clear then that there are definite relations between 

 fishes and plankton organisms, and that it seems possible with 

 fuller data to correlate some of the movements of fish with the 

 distribution of plankton. There is thus a reasonable probability 

 that an increased knowledge of the minute life of the sea may 

 be directly useful in connection with the regulation of fishing 

 industries. 



Plankton investigation in relation to the fluctuations of 

 fisheries is now being carried on throughout the seas of North- 

 west Europe, and it has been decided by the International 

 Council for the organisation of the work that the nets to be 

 used for this purpose should be : — 



(1) Medium Apstein, gauze No. 20 [180 meshes per inch] 

 diameter of opening 16 cm. 



(2) Nansen net, gauze No. 3 [55 meshes per inch] diameter 

 of opening 50 cm. 



And these special nets, we at Port Erin, like other investi- 

 gating bodies, will certainly have to use in the future for our 

 statistical observations. 



One of the resolutions of the International Council in 

 connection with this work is, naturally, that : — 



