1 839.] On the Distribution of European Birds. 23 



But although these secondary causes seem to have a certain influ- 

 ence in some places, yet that is far from being universal, all appearing 

 to be subject to some great principle hitherto undiscovered, and which 

 will probably remain for ever so. 



Nor is it alone in the organic kingdom that we find the distribu- 

 tion liable to vary from unknown causes. In the mineral kingdom 

 we observe phenomena of a similar nature. Thus we find, as has been 

 well remarked, " the geographical distribution of minerals to be 

 very different from mountain rocks ; we do not find the same species 

 everywhere, on the contrary, they seem to have many kinds of distri- 

 bution, in this respect approaching more nearly to what we observe in 

 the physical arrangement of animals and vegetables on the surface of 

 the earth." 7 



It is foreign to our purpose at present to give all the methods which 

 have been proposed by Humboldt, Latreille, Fabricius, Swainson, &c. 

 in order to point out the erroneous grounds upon which they are based 3 

 but shall at present confine our attention to that one most recently 

 given, viz. by Swainson ; and as he has entered into some detail, in 

 regard to the birds of one of his divisions, allowing us an opportunity 

 of refuting his statements, we shall therefore direct particular atten- 

 tion to it ; we are the more induced to do so, as no person has 

 ventured to point out the erroneous views of this author, which seem 

 to have been based upon a few and unsatisfactory data. 



By Mr. Swainson the globe has been divided into a series of zoological 

 regions or provinces, denominated, 1st. the European or Caucasian ; 

 2d. Asiatic or Mongolian; 3d. the American; 4th. the Ethiopian or 

 African ; and, 5th. the Australian or Malay. In the European or 

 Caucasian province he includes the whole of Europe properly so called, 

 with part of Asia Minor and the shores of the Mediterranean. In Nor- 

 thern Africa, he states, the zoological peculiarities of this region begin to 

 disappear ; they are lost to the eastward of the Caucasian mountains, 

 and are blended with those of Asia and America to the north. 2. The 

 Asiatic range comprehends the whole of Asia east of the Ural 

 mountains, which form a natural and well defined barrier between 

 the two Continents, The chief seat of this zoological region is, he 

 states, probably in Central Asia; its western confines blend into 

 the European towards Persia, and disappear in the west of the 

 Caucasian chain ; it is united to the African range among the provinces 

 of Asia Minor, and is again connected with Europe, and also with 

 America, by the arctic regions of the three Continents ; finally, its 



7 Jameson, Werner Trans. Annals of Phil. vol. vi, p. 301. 



