« ii aaww i ii >- 



Plate IV. Plankton nets at sea. 



(a) The i-mecre townet; it is fastened by a non-slipping knot in a chain to a wire cable that 



continues to a similar net at a greater depth. 



{b) The Hensen net after being hauled vertically. 



Photographs by (,i) N. T. Nicoll, (b) James Fraser 



