316 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
‘“PuLLey’”’ SurFace Net. 
Both last year and this year we have been struck on 
occasions, when watching the action of the surface nets 
in a rough sea, with the manner in which they appeared 
to bank up the water in front when meeting a wave 
and then let the line he slack for a few seconds when the 
wave had passed—both actions being equally detrimental 
to that normal and constant straining of the water which 
is desired. Consequeatly, when Mr. Drew was assisting 
in the plankton work on the yacht in August he fitted up 
one of the surface nets with a pulley fixed to the mizzen- 
mast in such a way that when the net took the strain of 
a wave more line was let out to keep the pull as nearly 
as possible constant, and the line was taken up again as 
the strain was relieved between two waves. This 
“Pulley ’ net was used on all occasions during August 
when there was any sea running—with the results shown 
in a column of the table on page 317. 
This shows that on most occasions (12 out of 17) the 
‘Pulley ’ net caught more, and frequently a great deal 
more (up to more than 8-fold), than the ordinary surface 
net of the same mesh. 
Whether somewhat the same regulating effect upon 
the pressure of water on the net could be produced by 
adding a truncated funnel of canvas to the front of the 
net, like that of the Hensen and other quantitative nets, 
is worthy of trial; and all the surface and other nets to 
be used on the yacht at Port Erin during 1909 are now 
being fitted with such canvas fronts, which will diminish 
the opening of the net from 15 inches to 6 inches diameter. 
Comparison oF NEw anv Op Surrace NEts._ 
Kofoid, in his work on the plankton of the Illinois 
River, found that a new net catches at least 50 per cent. 
