447 
still in movement, and the water with the detritus and the orga- 
nisms may then be sifted off. On repeating the process one may, of 
course, secure a much greater percentage of the organisms found 
in the sand. The result was again fully up to the expectations, an 
enormously rich fauna of small organisms e. g. Nematods, Planari- 
ans, Ostracods, Copepods (especially Harpacticids) and Infusorians 
being found to inhabit this upper layer of the sand. — The same 
method was also used on the sandy beach of the West coast of 
Jutland, where the waves of the North Sea beat with full force 
— and even here a rich fauna of micro-organisms was found to 
live in the sand. (Unfortunately there has been no opportunity 
of having all this rich material worked up). 
During the Danish Expedition to the Kei-Islands I used this 
method of sifting through a fine silk net samples of the upper layer 
of the bottom on localities of various character (— muddy flåts, 
sandy flåts etc. —) always with very fine results — but with regard 
to the microfauna of the bottom at greater depths there was only 
the old, unsatisfactory method of sifting small samples of the con- 
tents of the trawl through a silk net. 
Last year, on seeing a friend of mine using an apparatus devised 
for the purpose of catching micro-organisms from the bottom (cf. 
Ru tt ner. “Ober einige bei der Untersuchung der Lunzer-Seen 
verwendete Apparate und Geratschaften”. Internat. Rev. Hydrobiol. 
VI. 1913, p. 60—61) I was again led to take up the problem, not 
thinking the said apparatus sufficiently efficient for my purpose. 
The apparatus which I shall here describe (Fig. 1) was the result 
of my considerations. 
The first clairn, evidently, is this that the apparatus must be 
prevented from sinking too deep down into the soft mud. This 
is obtained by means of a thin zinc-plate, bent upwards at the 
anterior end like the runner of a sledge. But in order to prevent 
the risk of the apparatus coming down on the wrong side, a pair 
of such plates are fixed together, so that both sides are acting 
equally well. Between the two plates a silknet is hung, attached 
to a rectangular frame, which is fixed to the anterior edge of the 
plates by means of a string; for this purpose there is a hole at 
each side of the plate at the upwards bent edge. The two plates 
are connected with each other at the anterior end only in this 
