1918.] Platycercine Parrots of Australia. 123 



at one (tlie southern) limit it takes on its mature plumage, 

 if not from the nest, at least very soon afterwards. In other 

 parts of its range, immature specimens are much more 

 plentiful than adults, and it is recorded that they commonly 

 breed in the immature plumage. Keartland concludes that 

 males do not take on the mature plumage until two years 

 old, and that females continue in the immature state much 

 longer. There are further notes that sometimes the young 

 in the nest are plumaged as the adult, but more evidence of 

 this is required. However, at the eastern limit, and geo- 

 graphically not very distant from the southern end of its 

 range, the xanthochroistic element has regained strength and 

 the scarlet has become orange. This has continued in some 

 cases so that fully adult birds have been mistaken for the 

 xanthochroistic species living close by. We have here a 

 representative species and a representative subspecies very 

 closely approaching each other, through the revival of the 

 dominating element. 



Thirdly, coincident with these species is a third, in which 

 the erythristic and xanthochroistic elements have developed 

 without interference, though the cyanistic has been sup- 

 pressed. In this species the cheeks are white, the head and 

 breast scarlet, lower breast golden yellow, abdomen green, 

 under tail-coverts scarlet ; the back scalloped with golden- 

 green, rump yellowish green, and tail green. 



Little variation is seen in this species, which ranges into 

 Tasmania. The most important point is that it seems to be 

 getting brighter-coloured, and is increasing owing to the 

 destruction of bush, it having been christened " a bird of 

 sunshine.^' "VYe may conclude that here the xanthochroistic 

 element is developed nnder sunlight, but this would not 

 account for the yellow cheeks of the western form nor the 

 yellowish underparts of the Tasmanian species (catedonicns), 

 while this species (exitnius) ranges into Tasmania and the 

 yellow becomes more green. So far as I can discover, the im- 

 mature take on the mature plumage from the nest, proving 

 that this is the most specialized of the southern species. 



The two northern species can be treated together, as they 

 have many peculiarities in common ; in both the immature 



