DISTRIBUTION AND LOCATION 



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Notacanthidae. Several families of the soft finned fishes 

 (Malacopterygii) contribute more or less largely to the abys- 

 sal fauna. In the Stomiatidae, considered as distinct from the 

 Sternoptychidre, many of the species are certainly inhabitants 

 of deep water but with regard to others, as to many other 

 species in other families, the records of the depths at which the)' 

 have been obtained are open to serious doubt. The dredge or 

 trawl was open during its ascent to the surface, and therefore a 

 fish taken in it might have been captured at any depth between 

 the bottom and the surface in the course of the ascent. When 

 a fish like Astroncsthes niger is frequently taken at the surface 

 and also is found in a dredge which has been on the bottom at 

 a depth of 2500 fathoms it is difficult to believe that it can 

 actually live under such different extremes of temperature and 

 pressure, and such species must for the present be considered 

 to be pelagic, though ranging perhaps to some hundreds of 

 fathoms from the surface. The other species of the Stomiatidae 

 seem to be truly abyssal, some of them, such as Malacosteus 

 indicus, being among the most extraordinary deep-sea fishes 

 known. The genera are numerous, Stomias, Macrostomias, 

 Echiostoma, Opostomias, etc. ; they have elongated bodies with 

 small tail-fins, large mouths and formidable dentition, with a 

 long barbel under the chin. The Sternoptychidae having a com- 

 pressed body and silvery colour have more the appearance of 

 pelagic than of deep-sea fishes, but some of them range, accord- 

 ing to the records, from 100 or 200 fathoms to depths between 

 1000 and 2000 fathoms ; it is doubtful if any of them descend to 

 more than a few hundred fathoms from the surface. Belonging to 

 the family Salmon idae are four genera which live in deep water ; of 

 these Argentina occurs in moderate depths down to 200 fathoms 

 in the Atlantic while the numerous species of Bathylagus are 

 true abyssal forms, most of them having been taken only at 

 depths between 1000 and 2000 fathoms. Of the eels or Apodes 

 three families are inhabitants of the greatest depths, and it can 

 scarcely be doubted that they live actually at the bottom, though 

 here again we have the difficulty of the enormous range of 

 depth of the same species. These families are the Nemichthyi- 

 dae, Synaphobranchidae, and Saccopharyngidae. Nemichthys 

 has been taken in the Atlantic at depths from 216 to 2369 

 fathoms but most frequently at the more moderate depths. 



