828 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
Dinoflagellata in the bay were about a month later in 
1908, but they attained a higher level. The Copepoda 
on the other hand did not reach so high a point in the 
bay this year. For further details in regard to these, and 
also as to the occurrence of other groups compared with 
the previous year, reference must be made to the body of 
the Report. 
(8) Some points which might vitiate results have 
occurred to us in the course of our work, or have been 
suggested by critics. These we shall now briefly consider. 
1..The difference between the two sides of the 
ship.—It has been suggested that similar nets hauled 
simultaneously on the port and starboard sides may differ 
in catch because of the disturbing effect produced by the 
boat upon the surface water and its contained organisms. 
No doubt when the ship is broadside on to any wind, tide 
or sea the windward and leeward sides might yield some- 
what different hauls in the surface nets; but such 
conditions were not present in our experiments. The 
surface nets were towed close together over the stern, and 
the boat was kept head to wind and sea; consequently the 
nets were never one to windward and one to leeward, and 
both received the same amount of exposure or shelter as 
the case might be. It was only when using the vertical 
nets (Hensen and Nansen) hauled up from deeper strata 
that one was worked on each side of the ship, which was 
then kept as nearly stationary as possible with her head to 
the sea or wind, and in these cases, as the nets were 
generally used to collect samples of the deeper strata only 
and were closed at ten fathoms from the surface, any 
disturbance of the surface fauna due to the ship would not 
affect their catch. 
2. The effect of the ship’s screw-propeller upon the 
eatch of nets towed astern,—In a review of Part J 
