244 FISHES. 



south of Japan, where two Bagrina (Fseudohagrus aurantiams 

 and Ziocassis longirostris) have established themselves foi' a 

 considerable period, for both are peculiar to the island, and 

 have not been found elsewhere. 



In the east, as well as in the west, the distinction between 

 the Europo-Asiatic and IS'orth American regions disappears 

 almost entirely the farther we advance towards the north. 

 Of four species of the genus Salmo known from Iceland, one 

 (;S^. salar) is common to both regions, two are European {S. 

 fario and S. alpinus), and one is a peculiarly Icelandic race 

 {S. nivalis). As far as we know the Salmonoids of Greenland 

 and Baffin's Land they are all most closely allied to European 

 species, though they may be distinguished as local races. 



Einally, as we have seen above, the Europo-Asiatic fauna 

 mingles with African and Indian forms in Syria, Persia, and 

 Afghanistan. Gapoeta, a Cyprinoid genus, is characteristic 

 of this district, and well represented in the Jordan and rivers 

 of Mesopotamia. 



Assuming that the distribution of Cyprinoids has taken 

 its origin from the alpine tract of country dividing the Indian 

 and Palaearctic regions, we find that this type has found in the 

 temperate region as equally favpurable conditions for its devel- 

 opment as in the tropical. Out of the 360 species known to 

 exist in the Palaearctic regions, no less than 215 are (Jyprin- 

 oids. In the countries and on the plateaus immediately 

 joining the Himalayan ranges tliose m(junt;i,in i'orms which 

 we mentioned as peculiar to the Indian Alps abound and 

 extend for a considerable distance towards the west and east, 

 mixed with other Cyprinina and Cohitidina. The represent- 

 atives of these two groups are more numerous in Central and 

 Eastern Asia than in Europe and the northern j)arts of Asia, 

 where the Leuciscina preilominatc. Jbramidind or Breams 

 are more numerous in the south and east of Asia, but they 

 spread to the extreme north-western and northern limits, to 



