Distribution uf Birds. 519 



birds, is not so easily differeutiated. Although, as Mr. 

 Wallace has shown, our knowledge of this subject has been 

 much improved since my essay was written, in consequence 

 of the great advances made during recent years in the inves- 

 tigation of the birds of Central Asia, I think that this state- 

 ment still holds good, but not to so great an extent as at the 

 time when I made it. In the Palaearctic Ornis generally 

 the Sylviid^ or Warblers probably play the most important 

 part amongst Passerine birds. According to Mr. Wallace^s 

 tables, no less than 14 genera of this family are either essen- 

 tially or characteristically Palsearctic. Of these, Locustella, 

 Daulias, and Erithacus are good examples. Others are 

 Sylvia, Ruticilla, Regulus, and Accentor, though these are 

 not quite so exclusively Palsearctic. 



A second Passerine group highly characteristic of the 

 Palaearctic Region, though by no means exclusively confined 

 to it, is the Fringillid.e, containing the Finches and Bunt- 

 ings. At least 12 genera of this family are nearly or quite 

 restricted to the Palaearctic Region. Of these, Fringilla, 

 Pyrrhula, and Emberiza are good illustrative forms. The 

 CoRviD^ or Crow family is a third Passerine group very 

 characteristic of the Palnp.arctic Region, though some of the 

 genera are found in nearly every other part of the world. 

 Fregilus, Podoces, Cyannpica, and Garrulus are four well- 

 known forms of Palaearctic Corvid^. 



But the most magnificent group of the Palaearctic Ornis 

 is certainly the Phasianid^e, which is highly developed all 

 through its central portion. Many of the more splendid 

 Game-birds belong, it is true, to the Oriental Region ; but 

 at least five or six of the most remarkable genera are exclu- 

 sively Palaearctic. Such, for example, are Crossoptilon, 

 Luphophorus, Pucrasia, Phasianus, TUaumalea, and Ithaginis. 

 Thus, I think, on the Avhole, we may put down the four 

 families Sylviid.e, Fringillid.e, Corviu/E, and PnAsiANiDyE 

 as specially typical of the Palaearctic Ornis. As I shall show 

 further on, several other forms (such as Loxia, Sitta, Am- 

 pelis, Tetrau, Bonasa, Lagopus, and several genera of Ana- 

 Tin.Ej are common to the PaUearctic and Nearctic Regions, 

 ))ut are not found elscM'hcre, 



