Chun large 

 net. 



Prince of 

 Monaco's 

 pelagic 

 trawl. 



36 DEPTHS OF THE OCEAN 



Sars." We have found that if the appliance is sent down open 

 to a considerable depth, immediately closed and hauled in again, 

 it fails to capture anything, thus proving that vertical appliances 

 need not be closed while being lowered. 



For studying the vertical distribution of larger organisms 

 Chun used during the " Valdivia " Expedition a large silk net, 

 4 metres in length (Fig. 16). By lowering it to different depths 



Fig. 17.— Monaco's Pelagic Trawl, (From Steuer.) 



and comparing the catches so obtained, he could determine 

 at what particular depths the animals lived, and he succeeded 

 in collecting by this means valuable data as to pelagic deep- 

 water forms. 



The Prince of Monaco has also added largely to our 

 knowledge of the habitats of the larger pelagic organisms by 

 means of his pelagic trawl (Fig. 17), which is designed for 



Petersen 



young-fish 



trawl. 



Fig. 18. — C. G. Joh. Petersen's Pelagic Young-Fish Trawl. (From .Schmidt.) 



being towed horizontally through the water. In addition he, 

 made some remarkable captures of large pelagic animals, chiefly 

 cuttle-fish, by shooting whales and examining their stomach con- 

 tents, for the whale is still far more capable of catching living 

 marine creatures than any scientific appliance hitherto invented. 

 The young-fish trawl designed by C. G. Joh. Peterser 

 (Fig. 18) is a considerable improvement on the Prince 01 

 Monaco's pelagic trawl. It is very easy to construct, and 

 may be of any size or mesh. For catching young fish, etc., J 



