INTRODUCTION 7 



forms and intruders from the south. Bears, Beavers, 

 Sheep, and Deer similar; Prong -buck, Pouched Mice, 

 and Musquash peculiar ; Raccoon and Opossum, probably 

 derived from the south. 



6. — Paltearctic Region 



Xa.mc. — TraXaios, ancient, and a'/o«ro9, north, as embrac- 

 ing the whole northern area of the Old World. 



Extent. — Whole of the Eastern Hemisphere north of 

 a line on the south of the Atlas, and running eastward 

 through the south of Palestine and Persia, along the 

 Himalayas, through Central Asia and the centre of China 

 to the Pacific. 



Characteristics. — Absence of Monkeys, Lemurs, and 

 Frugivorous Bats; abundance of Carnivores — Ounce, 

 Lynxes, Wolves, Foxes, Bears, and Weasels; Rodents — 

 Marmots, Beavers, Pikas ; Ungulates — Sheep, Deer, 

 Chamois, and Musk-deer ; no Elephants nor Hyrax. 



This division of the Earth's surface into six regions was 

 first proposed by one of the authors of the present work 

 in an essay on the distribution of the Class of birds read 

 before the Linnrean Society in 1857 (9). It was further 

 elaborated and upheld in an address given to Section D. 

 of the British Association at the Bristol Meeting in 1875 

 (10), and in a Paper published in The Ibis in 1891 (11). 

 The same system was adopted by Mr. Wallace in his 

 standard work on " Geographical Distribution " (13), and 

 was there shown to be applicable to the other principal 

 groups of terrestrial animals. Moreover, the names then 

 bestowed on the six great primary Regions are now in 

 general use among naturalists in all countries. Mr. 



