bVZ TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



considerable and some time elapses during the lowering 

 and raising of the net from the bottom. The net is swung 

 over the ship's side, supported by its wire rope, which 

 passes over the " accumulator pulley " and then over the 

 recording apparatus on deck to the winch. When all is 

 in readiness, word is given to lower the net. An assistant 

 should note the moment that the mouth of the net reaches 

 the surface of the water, and shout a word of warning. 

 This is the zero, and at this moment another assistant w r ho 

 is observing the recording meter takes down the figures 

 exposed. To these figures the required depth should be 

 added, and then the net can be low r ered until the meter 

 gives the necessary numbers. 



When the net has been hauled again to the surface, 

 it is held over the ship's side and well washed down with 

 a strong stream of water. This is most important, as a 

 great quantity of the catch is often lodged under the 

 mouth-piece lower ring. A strong stream of salt water 

 from the hose is by far the best method of w r ashing the 

 catch down into the filtering bucket, and if no steam hose 

 is available, a small hand pump w r orked on the deck is 

 better than using buckets. A separate filtrator is un- 

 necessary. After the net has been well washed and the 

 water allowed to run out until only a little remains in the 

 bucket, this is unscrewed and the catch can now be 

 removed and fixed. 



Preservation of the Catch. 



When preserving the catch it is advisable to remove 

 as much sea water as possible, and to use a reagent that 

 will be simple in application and render the organisms 

 easy of identification. For this purpose 90 per cent, of 

 alcohol is used directly, it having proved the most con- 

 venient for ordinary purposes in quantitative work. It 



