FISHES- REGAN. 33 



members of the family ; two genera are peculiar to the Antarctic, two common to the 

 Antarctic and Magellan, four peculiar to the Magellan District, one common to 

 Magellan and Argentina, and one peculiar to the last-named. 



The Magellan District is the headquarters of the southern Zoarcidae, which may 

 have reached it originally from the north along the American coast, perhaps migrating 

 in rather deep and cold water. It is of interest to note that no Zoarcidae are known 

 from the South Temperate and Subantarctic Zones outside the Argentine and Magellan 

 Districts. Evidently the southern coast fishes of this family have been able to extend 

 their range only along a nearly continuous shore line ; this is in harmony with what 

 is known as to their breeding and development. 



TDK ANTARCTIC ZONE. 



This includes the coasts of the Antarctic continent and the islands that lie to the 

 south of the isotherm of <>'" C, with the probable exception of Macquarie Island. 



It is characterised by the complete absence of South Temperate types, by the 

 absence of Bovichthyidae and the great development of the other Nototheniiformes. 

 It is more sharply marked off than any other zone, the percentage of peculiar genera 

 being extremely high and that of species that ranee beyond its limits very low. 



Glacial District. 



This includes the coasts of the Antarctic continent and neighbouring islands. 

 together with South Georgia, the South Sandwich Islands, and probably Bouvet Island, 

 all lying within the extreme limit of pack-ice. About 90 per cent, of the coast fishes 

 of this district are Nototheniiformes and most of the rest are Zoarcidae, 



Nototheniidae. The Nototheniinae are represented by Trematomus (14 spp.), 

 Pleuragrammn (I sp.), Notothenla (6 spp.), and Dissostichus (I sp.). Eleginops is 

 absent. The two first-named genera are confined to this area; five of the six species 

 of Notothenia are peculiar, the exception being A. cor'dceps, which ranges to Kerguelen. 

 Dissostichus eleginoides is common to Graham band and Magellan. 



The Harpagiferinae (Artedidraco, Dolloidraco, Histiodraco, Pogonophrym, Harpa- 

 gifer) are confined to this district, with the exception of Harpagifer bispinis, which 

 extends also to the Kerguelen and Magellan Districts. 



Bathydracoxidae are confined to the district. Bathydraco must be regarded 

 as oceanic, and probably the related genera Gerlachea, Racovitzaia and Prionodraco 

 should go with it ; but none of these has been found far from the coast of Antarctica, 

 the most northerly being B. antarcticus, taken midway between Wilhelm Land and 

 Heard Island. Parachaenichthys georgianus from South Georgia and Gymnodraco 

 acuticeps from the coasts of the Antarctic continent may be reckoned as coast fishes. 



Chaenichthyidae are characteristic, the only extralimital forms being the two 

 species of Chaenichthys (Kerguelen) and Champsocephalus esox (Magellan). 



