SCLATER ON THE GENERAL DISTRIBUTION" OF AYES. 137 



be extending the limits of this communication too far to attempt 

 to go into these at the present time. 



I. PALiEARCTic Region (Pegio Palcearctica) . 



Extent. — Africa north of the Atlas, Europe, Asia Minor, Persia 

 and Asia generally north of the Himalaya range, upper part of the 

 Himalaya range ?, northern China, Japan and the Aleutian Islands. 

 Approximate area of 14,000,000 square miles. 



Characteristic forms. — Sylvia, Luscinia, Erythacus, Accentor, 

 Regulus, Podoces, Fregilus, Garrulus, Emberiza, Coccothraustes, 

 Tetrao. 



It cannot be denied that the ornithology of the Palsearctic or 

 great temperate region of the Old World is more easily charac- 

 terized by what it has not than by what it has. There are certainly 

 few among the groups of birds occurring in this Region, which 

 do not develope themselves to a greater extent elsewhere. For 

 \ve must acknowledge that the most productive seats of animal life, 

 where all the bizarre and extraordinary forms that the Naturalist 

 best loves are met with, lie under the suns of the tropics, and 

 far removed from temperate latitudes. The most prevalent forms 

 among the Passeres, of the Palaearctic Region, are perhaps the plain 

 dull-coloured Sylviince, distinguished rather for their melodious 

 song than by any external beauty of plumage or singularity of form. 

 Upwards of 35 species of this subfamily occur in the ornithology 

 of Europe alone ; and when Northern Africa and the whole North 

 of Asia are taken into calculation, the number would be consi- 

 derably increased, and this Region may be considered the true 

 focus of the group. 



The genus Erythacus would be perhaps as good a representative 

 genus as any as a type of Palsearctic ornithology ; a second 

 species {Erythacus aJcahige) occurring at the eastern extremity of 

 the Asiatic continent, and there beautifully representing our 

 common Robin. True Emberiza is likewise very characteristic of 

 the temperate portion of the Old World, nearly the whole of the 

 known species being found in Europe or Northern Asia. Ac- 

 centor is perhaps more strictly a northern Himalayan form, with 

 several representatives within the Palsearctic Region ; but Fregilus, 

 Podoces, Garrulus, Tetrao, and numerous species of Anatidce are 

 likewise eminently noticeable as among the most typical forms of 

 Palsearctic ornithology. 



LINN. PROC. — ZOOLOGY. 10 



