NEW SOUTH WALES 73 



myriads of feathered life from the dry west into 

 the eastern hills. That is the spasmodic west-east 

 irruption. This is in contradistinction to the regu- 

 lar annual bathic ascent to the higher levels of the 

 rivers and the plateaus. Autumn sees the return 

 of the birds from the Bassian or Victorian south, 

 into the plains of the Riverina. The cold of the 

 mountain heights is driving down the birds to the 

 lower levels again. 



New South Wales is visited annually by migra- 

 tory birds from Papua, which come to nest, as well 

 as by species from Siberia which come to winter, 

 but not to nest. From the south, the coast of New 

 South Wales is visited by vast numbers of sea 

 birds which pass northward in the winter, on their 

 way to the "far east" (Chosan). 



The rich western half of New South Wales, being 

 subject to drought, demands a sweeping exodus of 

 birds for a year or two together. The compensating 

 balance is a flood, when hundreds of millions flock 

 back to what is now one of the richest centres in 

 the world ; with an abundance of food and water 

 for the birds. 



There is also an annual migration from the north 

 which would be diverted in this time of drought, 

 or the birds would pass through into Victoria and 

 eat up everything, thus destroying the balance. 



The distribution of the birds of New South 

 Wales is more variable than with any other portion 

 of the continent of Australia. These are the repre- 



