SOUTH AND CENTRAL AUSTRALIA 185 



COLOUR GRADES 



(Plate 3, Fig. 78) 



1. Genus; 3. Species; 3. Race. 



To know a bird and get definition we look quickly 

 at the colours to see the scheme. After a moment's 

 hesitation we decide the genus to be such or such; 

 perhaps a genus of honey-eaters. The colour 

 scheme may be spots, streaks or splashes, or defin- 

 ite solid areas that will change or vary in intensity 

 among its species. These will always be true to 

 colour, even if varying in quality. It is this vari- 

 ation in quality that gives us the race which is not 

 quite the species. It shows a definite difference in 

 colour or form due to differences in country or 

 climate. 



A good example of a species is given in map 79, 

 5, and its five races 4, 3, 2, 1, a, lessening in inten- 

 sity from 5 to 1 — a, 5 being larger than 1. It is the 

 White-plumed Honey-eater. Another race is a, 



b, c, the Lesser White-plumed Honey-eater (P. 

 leilavalensis). The points of interest are that it 

 is a smaller bird than the southern bird and has 

 a brighter coloured head. Both these points are 

 in keeping with a law applied to nearly all birds 

 having a long range of habitat north and south e.g. 

 Cloncurry "a," Central Australia b, Flinders Range 



c. If it had extended south to 6 it would have lost 

 its bright head colour. 



