JULY. 137 



results on clear frosty nights in winter, though boating at 

 such times is neither particularly warm nor exciting. 

 Recently, when out with the trawling steamer in Tasman 

 Bay, I got very good results on two warm calm days, 

 but unfortunately on the last of these a little breeze sprang 

 up and my net went to pieces. On a dark still night, after 

 the net has been over the side for an hour or more, it 

 is drawn on board and turned inside out into a jar of clear 

 sea water. In the process the edges and lining of the net 

 gleam with bands and points of silvery nebulous phos- 

 phorescence, many of the smaller shining points being due 

 to organisms so minute that they cannot be made out 

 without the aid of a good lens. It is to be regretted 

 that to make any complete scientific investigation of these 

 little animals it is necessary to kill and preserve them ; for 

 they cannot be kept alive in confinement unless one has 

 a well aerated aquarium, and even then they mvist be taken 

 out of the tank and be placed in a small drop of water for 

 close examination. The colours and forms of many of them 

 are wonderfully beautiful, but the exquisite tints of the 

 living creature, as well as their phosphorescence, fade and 

 disappear in death. It is possible for a time to preserve 

 many of the hues in such a medium as formalin, but the 

 best general preservative is alcohol, and this destroys 

 nearly all colours and reduces all transparent organisms to 

 an uniform yellowish-white opacity. 



The number and variety of the living creatures which are 

 thus found floating in the ocean are very great, and quite 

 bewildering in their complexity of form. Probably the 

 most abundant both in kind and in individuals are small 

 Crustacea, but, in addition, delicate little jelly fishes, a few 

 worms, an occasional pipe fish, and the floating eggs of 

 several kinds of fish, are taken, as well as a few vegetable 

 organisms. 



Of the Crustacea, the commonest forms belong to the 

 family known as the Copepoda (or oar-footed). These are 

 usually very minute animals from a fiftieth to a tenth of an 

 inch in length, furnished with long sweeping antennae in 

 front, with several pairs of beautifully branched plume-like 



