THE PALuEARCTIC REGION 187 



whole of Siberia north of the great mountain ranges 

 together with the island of Saghalien, and perhaps, too, 

 the Japanese island of Yezo. In this Sub-region must 

 also be included Asia Minor, the Caucasus, and the Elburz 

 mountains. 



2. The Eremian Sub-region, including the north of 

 Africa, Northern Arabia, the greater part of Persia and 

 Afghanistan, and the great desert of Central Asia, ex- 

 tending from the steppes of Southern Russia as far as 

 Manchuria. 



3. The Chinese Sub-region, embracing the greater part 

 of China proper, Southern Manchuria, and Japan, and 

 extending westward to Western Tibet and the top of the 

 southern slopes of the Himalayas. 



The boundaries of these Sub-regions will be best under- 

 stood by referring to the accompanying map (Plate VII., 

 p. 196), in which they are approximately delineated ; but it 

 must be always understood that it is in most cases quite 

 impossible to draw a hard and fast line as the boundary 

 between two adjacent Regions on land. 



Section IV. — The Europasian Sub-region 



The Europasian Sub-region contains the great tem- 

 perate forest-area of the Northern Hemisphere. In its 

 western part, at any rate, this has been considerably 

 modified by the hand of man, but in primaeval times the 

 forests probably extended almost without break from the 

 Bay of Biscay to Kamtchatka. 



The Europasian fauna is not very rich ; it comprises 

 fifty-seven genera of Mammals, of which four only are 



