FISHES FROM THE SEA-BOTTOM 



423 



If we now consider what species of fish we obtain in our 

 trawlings along the continental slopes, we immediately recognise 

 different strata, each characterised by its peculiar fish-community. 

 It will be of interest to define the extent of these communities 

 by means of the species found most abundantly at different 

 depths, though there are no sharp limits between them, as it is 

 difficult to find even two kinds of fish (or other animals) having 

 in every respect the same distribution. It is thus obvious that 

 on the borders of the different communities recognised by us, 

 we shall find species belonging to neighbouring communities. 



We have already mentioned that the " Michael Sars " 

 caught some of the abyssal species along the continental slopes, 

 and the French deep-sea expeditions also gathered similar 

 information. We may then first consider the bathymetrical Bathymetricai 

 range of some of these peculiar bottom -fish living at the seali^shes?^^^' 

 greatest depths : — 



Bathymetrical Range. 

 Macriirus sckrorhynchus . . . from 540 to 3655 metres. 

 „ talismani, 



globiceps . 

 Ahpocephalus rosiratus . 

 Halosauropsis macrochir . 

 Synaphobranchus pinnatus ^ 



We see here a group of species which may occur in very 

 deep water as well as along the continental slope ; the upper 

 limit seems to be about 800 or 900 metres (about 450 fathoms), 

 although stray individuals have been caught in somewhat 

 shallower water. 



The main body of the fishes peculiar to the continental slopes 

 consists, however, of other species, which have not been captured 

 in the abyssal plain, though they have a wide distribution, like 

 the denizens of the abyssal plain, and resemble them also in 

 shape. Such are the following : — 



^ The fact that this form has been taken within such wide limits must, in my opinion, give 

 rise to the suspicion that it may really be caught in midwater ; perhaps it never actually occurs 

 in the abyssal area. 



