512 



DEPTHS OF THE OCEAN 



Fig. 356. 



Rhizocrinus lo/otensis, G. O. Sars. Magnified. 



(After Wyville Thomson.) 



whole extent. They thrive 

 well apparently on sandy 

 bottom, wherever it is covered 

 with fragments of shells, to 

 which they may attach them- 

 selves, and this is even better 

 seen in the central portion of 

 the North Sea. The " Michael 

 Sars " found hydroid-bottom, 

 of the kind described, on the 

 northern portion of the North 

 Sea plateau, on the Faroe 

 plateau east and west of those 

 islands and on the large bank 

 to the south of them, on the 

 Iceland-Faroe ridge, and on 

 the south-eastern Iceland 

 plateau. 



A number of species be- 

 longing to different groups, 

 which among the skerries and 

 in the western fjords of Nor- 

 way are littoral forms, or at 

 any rate only occasionally 

 descend below the lower limit 

 of the littoral zone, occur at 

 greater depths out on the 

 plateaus, where they are some- 

 times very plentiful. 



During the cruise of the 

 "Michael Sars" we found on the 

 eastern Faroe plateau, at a depth 

 of 1 10 metres, on sandy shell- 

 strewn bottom : Cucumaria fron- 

 dosa, Strongylocentrotus droba- 

 cktensis, Pandalus atmulicornis, 

 Pagurus bernJ tardus, Asterias 

 rubens, Mytilus modiolus, Bucci- 

 nuin undatuin, Alcyoniuvi digi- 

 tatum, and on the Faroe Bank, 

 south-west of the Faroe Islands, 

 at about 125 metres, Echinus 

 esculentus and OpJiiura albida. 

 On the banks around the Faroes 

 beyond the lOO-metres line there 



