Distribution of Birds. 517 



now (2), have started on altogether different principles, and 

 have divided up the earth's surface in an entirely different 

 way. I trust, however, that on the present occasion I may be 

 excused from discussing these different schemes. But I 

 may be allowed to point out with pride that the great 

 naturalist Alfred Russel Wallace, who has written the best 

 and most complete book that has yet been issued on the 

 geographical distribution of animals (3), has entirely adopted 

 the divisions which I originally proposed and the nomen- 

 clature consequent thereon *, and has based the whole of his 

 work upon the principles which I put forward in 1858. 



Mr. Wallace has well pointed out that, so long as we do 

 not violate any clear affinities or produce any glaring irregu- 

 larities, it is a positive and by no means unimportant advan- 

 tage to " have our principal regions nearly approximate in 

 size, and with easily defined, and therefore easily remem- 

 bered, boundaries,'' As he truly states, the most obvious 

 zoological division of the earth would be made by separating 

 the Australian Region from the rest of the world, there 

 being no doubt that the Australian fauna is by itself of 

 quite as great peculiarity as that of the whole of the rest of 

 the world taken together. But when this has been done we 

 have not advanced the subject very far, being only able to 

 say that a certain group of animals is '' Australian " or 

 *'non- Australian." A second great natural division may 

 readily be made by cutting off the Neotropical Region from 

 the rest of the world. After deducting the Australian 

 Region, it could easily be shown that the Neotropical 

 Region has more special groups of animals peculiar to 

 itself than the four remaining divisions of the world put 

 together. Upon doing this we should have three primary 

 divisions of the earth's surface, which I agree with 

 Prof. Huxley (4) and other writers in recognizing as of 

 tolerably equivalent zoological importance. But it would be 

 a great practical inconvenience to unite the whole of the 

 northern portion of the world under one designation, even if 



* With the exception of the alteration of the "Indian" Region into 

 " Oriental," as already mentioned. 



