218 AUSTRALIAN BIRD MAPS 



tion of the lowland to cross a mountain range thinly 

 covered with low-growing plants. 



All the coastal species in the text of map 99 are 

 found only in south-west Australia. The robin has 

 a small white frontal mark, originally pointed out 

 by the ornithologist, A. J. Campbell, while the 

 scarlet-breast of Eastern Australia has a large 

 white frontal mark. The Spine-bill of Eastern 

 Australia has no white brow, so that the develop- 

 ment of a white brow in Western Australia is 

 interesting. This is an example of what is con- 

 tinuously occurring amongst birds. 



The Ultramontane birds mentioned above have 

 no barriers to migration eastward for thousands 

 of miles, with the result that they have a broad 

 distribution. The Darling Range divides the coun- 

 try into western moist and eastern dry. In the 

 latter we have the Red-capped Robin which puzzles 

 us greatly by taking on a partly red throat, often 

 skipping a generation or two. It lives in the jam 

 country (Eucalyptus) a loose inland forest, while 

 on the coastal side another robin frequents the 

 giant jarrah country (E. marginata). The Bronze- 

 wing pigeon is an instrument of distribution for 

 the seeds of the "jam trees," while the honey-eaters 

 which associate in the high foliage of the jarrah 

 and karri gums cross fertilise the trees. Many 

 other proofs of this means of dispersal occur in the 



