230 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



net used at the same time, and a1 the same depth, on the 

 other side of the ship, caught twice as much material but 

 not a single specimen of the new Copepod. The surface 

 nets are also somewhat divergent in their results, while 

 the deeper weighted net has caught a very much larger 

 quantity of material, the greater part of which is clearly 

 made up of Copepoda both young and old — about ninety- 

 five thousand in all. 



Results of the Vertical Hauls. 



The two vertical closing nets we have used from the 

 " Ladybird " are the Petersen-Hensen and the Nansen, 

 both of which have now been thoroughly tested, and have 

 given on the whole good results. The ring of the 

 Petersen-Hensen net is 19 inches in diameter, and the 

 opening at the mouth into which the brass lids fit is 7j- 

 inches. The opening of the Nansen net (figs, o and 4) 

 is 14 inches. 



As a vertical closing net we prefer the JS'ansen 

 to the Petersen-Hensen. It is lighter and less compli- 

 cated (a matter of some importance in a rough sea), more 

 easily manipulated, less liable to failure in action, costs 

 less and generally catches more. The brass cylinder at 

 the lower end is, however, too small, and might be 

 improved in other ways. 



These two vertical closing tow-nets are obviously not 

 comparable one with the other. Their dimensions are 

 different, and the results of the hauls are usually also very 

 different, the Nansen net almost invariably catching more 

 than. the Hensen. The maximum amount for the Hensen 

 is 64' 5, while the maximum for the Nansen is more than 

 twice as much, namely, 164 c.c. These two nets were not 

 used for the purpose of obtaining results that would be 

 comparable, but were used for the purpose of testing the 



