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

CHAPTER XIII.THE AUSTRALIAN EEGION.The Australian is the great insular region of the earth. As awhole it is one of the best marked, and has even been consideredto be equal in zoological value to all the rest of the globe ; butits separate portions are very heterogeneous, and their limitssometimes ill-defined. Its central and most important massesconsist of Australia and New Guinea, in which the main featuresof the region are fully developed. To the north-west it extends toCelebes, in which a large proportion of the Australian charactershave disappeared, while Oriental types are mingled with themto such an extent that it is rather difficult to determine where tolocate it. To the south-east it includes New Zealand, which isin some respects so peculiar, that it has even been proposed toconstitute it a distinct region. On the east it embraces thewhole of Oceania to the Marquesas and Sandwich Islands, whosevery scanty and often peculiar fauna, must be affiliated to thegeneral Australian type.Australia is the largest tract of land in the region, beingseveral times more extensive than all the other islands combined,and it is here that the greatest variety of peculiar types havebeen developed. This island-continent, being situated in thetrack of the southern desert zone, and having no central mountainsto condense the vapours from the surrounding ocean, has alarge portion of its interior so parched up and barren as to bealmost destitute of animal life. The most extensive tract offertile and well-watered country is on the east and south east,