424 DEPTHS OF THE OCEAN chap. 



These appear to be representatives of the fauna peculiar to 

 the steepest part of the slope, from 700 to 1500 metres (400 to 

 800 fathoms). 



The " Michael Sars " captured on the Atlantic slope, in 

 depths between 800 and 2600 metres, over 1200 fishes, the 

 relative abundance of the different forms being as follows : — 



569 fishes, or about 47 per cent, belonged to Macruridse. 



393 „ 33 ., ,, Gdid\<l2d{Mora,Anti?nora, Lepidio?i, 



Halargyreus). 

 66 ,, 6 ,, ,, Alepocephalid^. 



47 „ 4 ,, „ Sharks {Cefttrophortts, Chimcera, 



Etmopterus). 



The remaining 10 per cent consisted offish represented by 

 only a few individuals (Notacantktcs, rays, and others). 



In about 400 to 500 fathoms (700 to 900 metres) we meet 

 with forms having their lower limit in this region, which live in 

 greatest abundance at 200 to 300 fathoms. As instances may be 

 mentioned : — 



Bathymetrical Range. 

 Sebastes dactylopterus . . . from 75 to 975 metres. 



Motella macrophthalma . . . „ 146 ,, 987 „ 



Hoplostethus mediterranettm . . „ 140 ,, 1435 ,, 



In about 300 to 350 fathoms (550 to 650 metres) we meet 

 with real representatives of the fauna of the coast banks. The 

 following are some of these species, found in deep water by the 

 French expeditions, with their bathymetrical range : — 



Bathymetrical Range. 

 Merluccius vulgaris (hake) . . from 65 to 640 metres. 



Gadici/lus argenieiis . . . ,, 411 „ 550 „ 



Zeugopferus megastoma . . . „ 60 ,, 560 ,, 

 Dentex macrophthalmus . . . „ i2o„46o „ 



In these depths we thus find in the same hauls representa- 

 tives of two entirely different faunas, and we must therefore 

 consider this region as an intermediate belt. 



Before attempting to describe the fauna of the coast banks, I 

 wish to discuss some questions of general importance arising 

 from the examination of animal life on the continental slopes. 



In his report on the deep-sea fishes of the " Valdivia " 

 Expedition, Brauer gives a very able and interesting review of 

 the general laws governing the geographical distribution of 

 these fish, particularly the Macruridae. While the genus 

 Macruriis is found in all the oceans, he considers most of the 

 species to be local. Of 116 species of Macruridae he has so far 



