The geographical distribution of animals, with a study of the relations ...

;CHAPTER X.THE PALiEAECTICREGION.This region isof immense extent, comprising all the temperateportions of the great eastern continents. It thus extends fromthe Azores and Canary Islands on the west to Japan on theeast, a distance not far short of half the circumference of theglobe. Yet so great is the zoological unity of this vast tract,that the majority of the genera of animals in countries so farremoved as Great Britain and Northern Japan are identical.Throughout its northern half the animal productions of thePalaearctic region are very uniform, except that the vast elevateddesert-regions of Central Asia possess some characteristic formsbut in its southern portion,we find a warm district at each ex-On the west we havetremity with somewhat contrasted features.the rich and luxuriant Mediterranean sub-region, possessing manypeculiar forms of life,characteristic of the Ethiopian region.as well as a few which are more especiallyOn the east we have thefertile plains of Northern China and the rich and varied islandsof Japan, possessing a very distinct set of peculiar forms, withothers belonging to the Oriental region, into which this part ofthe Palaearctic region merges gradually as we approach theTropic of Cancer.Thus, the countries roughly indicated by thenames—Northern Europe, the Mediterranean district, Centraland Northern Asia, and China with Japan—have each wellmarkedminor characteristics which entitle them to the rank ofsub-regions. Their boundaries are often indefinable ; and thosehere adopted have been fixed upon to some extent by considera-