6o 



Isospondyli 



As in the Osteoglossida and in the Siluridce, the subopercle is 

 wanting in Pantodon. 



The Alepocephalida are deep-sea herring-like fishes very 

 soft in texture and black in color, taken in the oceanic abysses. 

 Some species may be found in almost all seas below the depth 



Fio. 48. Alepocephalus agassizii Goode & Bean. Gulf Stream. 



of half a mile. Alepocephalus rostratus of the Mediterranean 

 has been long known, but most of the other genera, Talis- 

 mania, Mitchillina, Conocara, etc., are of very recent discovery, 

 having been brought to the surface by the deep-sea dredging 

 of the Challenger, the Albatross, the Blake, the Travailleur, 

 the Talisman, the Investigator, the Hirondelle, and the Vio- 

 lante. 



