INTKODUCTION. 



Ever since the publication of the 'Catalogue of Birds' I have kept a 

 record of the additional species described, and my notes will be published 

 in the supplementary volumes of the ' Catalogue ' to be issued shortly. 

 The writing of these notes has been rendered the more easy by the 

 fact that for many years I have compiled the ' Aves ' portion of the 

 ' Zoological Record.' 



It gave me, therefore, great pleasure when the Trustees of the British 

 Museum consented to publish a new ' Hand-list of Birds,' since the need 

 of such a work has long been recognized by ornithologists. The present 

 compilation differs only from that of my predecessor, the Lite George 

 Kobert Gray, in that I have had the advantage of being able to refer to 

 the ' Catalogue of Birds,' where a full sjnonymy of each species will 

 be found. The geographical range is here given as concisely as possible, 

 and is based on the conclusions derived from the ' Catalogue,' instead of 

 being founded chiefly on the material in the British Museum, as was 

 done in Gray's ' Ilund-list.' The system of classification followed in the 

 present work is that proposed by myself in 1891, in my address to the 

 Second Ornithological Congress at Buda-Pest. I have seen no reason 

 to modify the conclusionfi there recorded in any material degree. 



I have ventured to incorporate in what appears to me to be their 

 natural position the extinct forms of birds ; but it is difficult to discover 

 all the descriptions of fossil birds, scattered as they are through so many 

 publications. In some of my volumes of the ' Catalogue ' fossil forms 

 are enumerated, but in most of the volumes no record of the extinct 

 birds has been attempted. My work in this direction has been 



