Distribution of BirfJs. 537 



Mr. Layard's excellent essay on the birds of New Caledonia 

 (85), little has been done to reduce our knowledge of this 

 subject into order. Mr. Seebohm, how^ever, has recently 

 turned his attention to this subject, and having acquired the 

 whole of the Messrs. Layard's extensive collection, has a good 

 basis to work upon, which will no doubt result in a valuable 

 work upon the Pacific Avifauna. 



5. The Hutooiiun Subregion. 



As I liavc shown in an essay upon the birds of the Sand- 

 wich Islands, published in 'The Ibis' for 1871 (86), the 

 Hawaiian Avifavma is so peculiar in its character that it 

 must necessarily be referred to a division separate from the 

 rest of the Pacific Islands. During the past twenty years 

 our knowledge of this subject has made great advances, and 

 Mr. Scott Wilson's recent expedition to the Sandwich Islands 

 has vastly increased it. Mr. Wilson's first number of the 

 * Aves Hawaiienses ' (87) has already been issued, and the 

 Avork when completed bids fair to give us an excellent and 

 accurate account of all that is yet known of the biids of the 

 Hawaiian Subregion. 



V. — The Nearctic Region {Regio Nearctica). 



(a) Extent. — America down to Southern Mexico, and 

 Greenland. 



(b) Characteristic Forms. — Many writers on zoo-geography 

 have treated the Nearctic Region as merely a piece of the 

 Palsearctic, and there are, no doubt, grounds upon which this 

 view may be supported. But as I have always maintained, 

 and as has been fully shown by Mr. W^allace, the Nearctic 

 Region, " although somewhat deficient in the total number 

 of its families, possesses a full proportion of peculiar and 

 characteristic family and generic forms," and may therefore 

 justly as well as conveniently be allowed full rank as a 

 Region. In this Region the Palsearctic element is certainly 

 strong; but its avifauna has been greatly modified by the 



