CHAPTER VIII 



THE FISHES OF THE DEEP SEA 



HE study of the animal life of the deep sea, 

 is mainly concerned with three categories of 

 creatures. The first of these, is that named 

 by Haeckel, Plankton, the organisms, mostly 

 minute, which float* on the surface of the open ocean. 

 Among the Plankton, young fishes may sometimes be 

 found, occasionally the young of shore fishes, carried 

 from their natural habitat by oceanic currents. Next 

 come the Pelagic forms, those moving freely in the 

 water near the surface, and choosing the open sea by pref- 

 erence. Besides whales and dolphins, many fishes are 

 pelagic. Among these are various large forms, as sharks 

 and numerous members of the mackerel family, as the 

 tunny, the albacore, the bonito and their relatives. The 

 smaller pelagic fishes usually go in schools, the larger ones 

 swim about singly. Among those in schools are certain 

 species of mackerel, and most of the flying fishes. All these 

 pelagic forms resort to certain regions, chosen bays and 

 straits usually within the tropics, for purposes of spawning. 

 From these regions they sally forth on more or less definite 

 predatory expeditions. Many pelagic fishes breed in the 

 Mediterranean and in the West Indies. Others find their 

 homes about the islands of Southern California, and in 

 Hawaii and Southern Japan. 



The third category of deep sea life, is that constituting the 

 bassalian fauna, or life of the depths. This includes forms 

 living below a depth of five hundred feet; some of them 

 swimming freely, others lying close to the bottom, or, in the 



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