300 DEEP SEA FISHES. 



The branchiostegal rays serve to distinguish this species from any other 

 at present known. 



NOTACANTHOIDS. 



The eleven known species of the Notacanthoids represent three genera, 

 Polyacanthonotus, Notacanthus and Lipogenys. So far as now determined 

 members of the group occur in the Mediterranean and the neighboring parts 

 of the Atlantic, in the northwestern Atlantic, at the south of Japan, at tlie 

 south of Australia and New Zealand, off the southwestern coasts of South 

 America, in Bering Sea, and, from the material at hand, in the eastern part 

 of the tropical Pacific. None have yet been reported from the Indian Ocean, 

 or from the southern Atlantic. The greatest depths were those for Polya- 

 canihonohis Challengeri Vaill, taken by the " Challenger," south of Yedo, 

 Japan, at 1875 and 1625 fathoms, and by the " Albatross," west of the Pribi- 

 lof Islands in Bering Sea, at 1401 fathoms, the nearest approach to which is 

 a depth of 1209 fathoms measured by the " Talisman " in the Mediterranean 

 Sea. All of the other depths are less than a thousand fathoms. As has 

 already been pointed out by Gunther in the case of Notacantlms sexspinis 

 some of the species are doubtful additions to the list of deep sea fishes. 

 Others have more of the appearance of such fishes as are commonly believed 

 to live at considerable distances from the surface at the intermediate depths. 

 In the case of a few there is little reason to doubt that they dwell near to or 

 at the bottom. 



This collection includes the types of a new species, described and figured 

 below, the nearest allies of which are Notacaidhus aiialis from the western 

 Atlantic, iV. Bonapartii from the Mediterranean and N'. 3Ioscleyl from the 

 southwestern coast of South America. 



