TASMANIA 159 



ISLAND DISTRIBUTION 



1. Racial; 2. Non-racial 

 (Plate 1, Figs. 6, 30; Plate 2, Fig. 61) 



Tasmania, King, Flinders and Kangaroo are four 

 young islands that regularly have the same species. 

 Most of them get the overflow from the main part 

 of the Bassian sub-region (N.S.W.-Vic.). Those 

 which have become stationary in Tasmania are 

 already subject to geographical effect. This gives 

 the racial differences. Food and forest; moist or 

 dry ; warm or cold ; and the feathers remain as they 

 are or darken. They deepen their plumage colour. 

 A species living on a large bushy swamp, rather 

 than on an open scrub, in a few generations 

 changes its colour sufficiently to make a race of 

 the species. There are many such examples that 

 have not yet been studied in Australia, and it is to 

 be the work of many all round naturalists to supply 

 the information. 



Map 67 associates the islands of Bass Strait with 

 South and South West Australia, through the 

 agency of the Cape Barren Goose. It is a unique 

 goose and there is one race of it; in South Western 

 Australia. 



The non-racial birds are the wanderers which 

 annually travel over many countries, and are 

 beyond local influences. The Grey Plover, Turn- 

 stone, Greenshank and several high-flying birds are 

 amongst them and thoroughly cosmopolitan. 



