SOUTH AND CENTRAL AUSTRALIA 181 



occasional Pipit or Bush Chat is seen. The granite 

 ranges are best for the majority of birds. The end- 

 less dry water courses lined with red gums (Eu- 

 calyptus rostrata) harbour Diamond Birds and 

 Tree-Tits. 



SOUTH AUSTRALIAN RACES OF 

 TIT-WARBLERS 



Many of the very small grey birds we see in the 

 creek scrub, dry hill sides, or away in the hot 

 country are Tit- Warblers. The common Yellow- 

 Tail is one. 



Together they make a very large assemblage or 

 genus and as they have got into all sorts of coun- 

 try and stayed there, the colour of the plumage has 

 come to be in sympathy with its surroundings. It 

 then becomes a race. Map 77 shows the races, as 

 well as we know them, in different parts in South 

 Australia. They comprise a central southern group 

 of races. 



The race extending from Musgrave Range, A, to 

 Murchison East, W.A., B, is remarkable in so far 

 as it extends over one thousand miles east to west 

 along an average rainfall zone of seven inches. In 

 South Australia the vegetation is mulga (Acacia 

 aneura) and it extends some great distance west- 

 ward. 



The Thick-billed Tit-Warbler (A. robustiros- 

 tris) is about the only bird to be found over wide 

 areas of this thousand miles. If there are any 



