SEA FISHERIES 149 



water from the Atlantic, both from the North- 

 west and through the English Channel. We 

 further believe that it will shortly be possible 

 to correlate the changes in volume of these two 

 streams (with the fish food contained in them) 

 with the climatic conditions of Europe and 

 America. The curious ebb and flow of the Gulf 

 Stream, its welling up and subsidence, closely 

 connected as these seem to be with the migration 

 of the herring, cod and haddock shoals in different 

 areas, has also received much attention. 



(n) We have investigated the character of 

 the sea bottom with great care, and can now form 

 as it were a geological map of an important 

 part of the North Sea. Connected with the 

 nature of the sea bottom is the kind of animals, 

 molluscs, Crustacea, etc., which it supports, and 

 which in their turn serve as food for fishes. All 

 these we have collected and identified, and we 

 have carried on a most extensive series of experi- 

 ments into the food of many different species 

 of fish in varying localities, and in the inter- 

 relation of one species with another either as 

 prey, competitors or enemies. 



(12) Amongst the most interesting of our 

 results is the mapping out of the bottom currents 



