xxiv INTRODUCTION. 



Nowadays where species of limited range are to be 

 found, the half-educated ornithologist is too often their 

 worst enemy, from his mistaken zeal in " accumulating 

 liberal series " for Museums. 



In birds of wide range, considerable differences are 

 often noticed between examples from different localities, 

 though, as these differences are not constant, they do 

 not constitute a specific distinction. Such local differ- 

 ences constitute what are known as local races ; thus 

 the large Siberian Goldfinches, commonly imported 

 into England in winter by dealers, are easily distinguish- 

 able from our own birds, but connecting links are easily 

 found in Continental specimens. 



The world is divided ornithologically into several 

 great regions characterized by the birds occurring there. 



The Palaearctic region includes the northern part of 

 the Old World. The Divers, Auks, and Grouse are 

 confined to this region, and it is the chief breeding- 

 ground of many groups, such as Warblers and Sand- 

 pipers, which often spend the winter much farther south 

 of it. Thrushes, Tits, and Finches are also partly 

 characteristic birds of this region, but are likewise found 

 over the whole world generally. 



The Nearctic region consists of North America, and 

 exhibits much the same characteristic types as the 

 above, with a mixture of South American forms ; but, 

 as most of these are migratory, it is hardly justifiable to 

 keep the regions separate, and the two combined are 

 often known as the Holarctic region. 



The Ethiopian region includes Africa south of the 

 Sahara, the country north of which belongs to the Palae- 

 arctic region. This contains many peculiar and charac- 

 teristic forms. Mouse Birds, Touracous, Wood Hoopoes, 

 Guinea Fowls, and especially the Ostrich, while Weaver 

 Birds, Francolins, and Hornbills are highly charac- 

 teristic of it, although not confined thereto, occurring 

 also'^in the next region. 



