INTRODUCTION. 



IN preparing this Hand-List our chief aims have been (1) to 

 give an up-to-date and useful account of the distribution at home 

 and abroad of all those birds which in our opinion are entitled to 

 a place on the British list, and (2) to give each bird its correct 

 scientific name in conformity with the Rules of the International 

 Commission on Zoological Nomenclature. 



In drawing up this account of the distribution of each species 

 in the British Isles we have had in view the necessity of giving such 

 details as will indicate to the student whether a bird is worthy of 

 special record on account of its general rarity, its scarcity in any 

 particular part of the country, or at some particular season of the 

 year, or because of the want of previous observations. For these 

 and other such reasons it has been necessary to treat some species 

 much more fully than others. The distribution abroad has been 

 given in more general terms, but here again a species of wide range 

 does not require so much detail as one of more restricted or unequal 

 distribution. Moreover our knowledge of the distribution of some 

 species is much more complete than that of others. 



The notes on migration refer chiefly to passage-movements or 

 are given in cases where the known migrations of a species are too 

 complicated to be treated in the distributional accounts. 



For various reasons nearly every bird on our List has been given 

 at one time or another more than one scientific name, and the 

 difficulty always has been to know by which name it should be 

 called. Nomenclature is proverbially a vexed subject, but there 

 is one necessity which all, however diverse their views, must agree 

 is of the first importance the necessity for uniformity ; not a 

 partial uniformity confined to British ornithologists or to any 

 other section of the ornithological world, for such a uniformity could 



