57 



agrees in many points with the northern iauna of the Old World, and 

 has been united with it by some authors ; but its peculiar types, and 

 those which it shares with South America, are too numerous for such an 

 arrangement. Its relations are exhibited in the following table : 



The special peculiarities of the Nearctic region are then chiefly seen 

 in the Fishes and Batrachia. In Birds and Mammals, its prominent 

 divergences from the northern regions of the Old World are seen in the 

 'lumerons representatives of forms which are characteristically South 



