I02 DEPTHS OF THE OCEAN 



Vertical to try at the same time some vertical hauls with our closing 

 oflnimah" nets. Accordingly, at Station 63 we made two series of hauls, 

 one with a silk net i metre in diameter, and the other with the 

 large 3-metre silk net {Fig. 89). 



These experiments merely resulted in our capturing the 

 species which occur most commonly, — a fresh proof that it is 

 difficult to become acquainted with the fauna when only vertical 

 hauls are made. A great many of the forms are too scarce to 

 be caught by such means, and can only be taken by long- 

 continued horizontal towing. In the case of the commonest 

 species, however, these vertical hauls do give an indication 

 of the vertical distribution as well as of the quantitative occur- 

 rence at different depths. It is advisable, therefore, to supply 

 a few particulars of our experiments with the large net : — 



Only 10 fishes were taken in a haul from 4500 metres up to 1500 

 metres, where we closed the net. All of them belonged to the species 

 Cydothone inicrodon. 



In a haul from 1350 metres up to 450 metres we got 44 fishes; 27 

 specimens of Cyc/othone mzcjvdon, 3 of C. signata, and 14 young fish 

 (stomiatids and others). 



In a haul from. 500 metres up to 200 metres some small specimens of 

 Cydothone signata and a number of young fish were caught. From 200 

 metres to the surface there were only young fish. 



This agrees with what we found when making horizontal 

 hauls. The black Cyclotkone 7Jzicrodon is only to be met with 

 in deep water, where the light-coloured C. signata is absent, 

 and C. signata occurs nearer the surface — from about 500 

 metres up to 200 metres — but has not been taken in depths less 

 than 200 metres. 



It is important to note how much fewer the individuals are 

 in the deepest hauls. Though we drew the net through 3000 

 metres (from 4500 up to 1500 metres), we only caught 10 

 fishes, while in the 900 metres of water from 1350 metres up to 

 450 metres we got 44 individuals, 27 of them belonging to the 

 same species as the 10 fishes from greater depths. 



Similar conditions appear to prevail in the case of the red 

 prawns, for in our deepest haul we caught only 1 1 large red 

 prawns, but in the haul immediately above it there were 35 

 individuals. This seems to indicate that the deepest water- 

 layers cannot at all compare in abundance of organisms with 

 the intermediate layers. 



At this station we also recorded a very large series of 

 hydrographical observations, namely, twenty water-samples and 



