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to collect about 15 samples on a voyage across the North Atlantic 

 at Long. 58° — 60° W. ; this will furnish one with Plankton from 

 the existing ocean-currents; (2) that as a rule there are no sharp 

 boundaries between these; still the dividing line between the North 

 Sea and the North Atlantic is clearly defined; (3) that the specimens 

 which inevitably remain attached to the meshes when collecting 

 several samples with the same net are of no consequence; (4) that 

 according to this method a somewhat different result is arrived at 

 regarding the relation between the quantities of the organisms 

 collected, than is obtained by the usual method, as the surface of 

 the small filtering gauze is very soon filled up , and is at last 

 completely blocked, so that many small forms are caught which 

 otherwise would escape, e. g. CoccoUthophora, Syracosphcera, etc. 

 (5) A comparison betAveen these collections and those gathered at 

 about the same time on the same route , and published previously 

 by Ostenfeld (1. с. 1900 Tab. IV, V) shows that a fairly good 

 conformity exists between the Plankton-associations. Further it is 

 clear that the point at Avhich every single organism occurs lies 

 further and further westward, if one reckons from the collections 

 made at the earliest time of the year to the latest. 



Finally, through these investigations we have arrived at the 

 result, that there cannot be proved to exist a strict connection 

 between the colour of the sea water and the nature and relative 

 quantity of the Plankton, still, on the whole, there is a general 

 connection, the usual rule being that a yellowish green water is 

 richer in Plankton than is the blue water. 



