I go 



ANIMAL LIFE OF THE DEEP SEA BOTTOM 



Spiny isopod crustacean (Arcturus) yVom 4,400 metres. Body five centimetres long. 



Kermadec and the other trenches, there is a marked similarity in the 

 composition of the fauna. This similarity may well prove to be still greater 

 when further fishing is carried out; but the varying food requirements of 

 the species may nevertheless result in differences (Fig. p. 192). 



Among the bristle-worms caught by the Swedish Deep-sea Expedition was 

 a new species, taken near the Azores and Canaries at 4,270 and 4,600 

 metres. We found this again on the opposite side of the globe in the Ker- 

 madec Trench, at four stations ranging from 6,140 to 6,960 metres. This 

 will serve as an example of a deep-sea cosmopolite; so far, other species 

 are known only from deep water in the Indo-Pacific region. But it 

 is a very remarkable fact that three species have been found in shallow 

 coastal water; apparently, therefore, they can tolerate enormous diffe- 

 rences of pressure and temperature. For the present, however, we must 

 presume that there are certain physiological differences between the stocks 

 of shallow water and of the abyss, differences which are not evident in 

 the external appearance, but are of the same character as the ones which 

 enable Professor ZoBell's deep-sea bacteria to thrive under high pressures 

 even though in outward form they are indistinguishable from surface 

 bacteria. 



