1918.] Platycercine Parrots of Australia. 119 



is becoming grey, and red tips are making their appearance 

 on the feathers, and it seems that this grey stage is becoming 

 fixed in the immature. 



Howevej', I had better place the facts of the coloration 

 on record and discuss their suggested evolution afterwards. 

 I will begin at caledonicus (PI. III. fig. 1), as I believe it to 

 be nearest the ancestral form. This species has a greenisli 

 coloration throughout, darker on the back and yellowisli 

 green below. A red frontal patch appears and the cheeks 

 have a bluish tinge, and there is a faint bluish shoulder-patch. 

 These are present in the young, but are indistinctly marked 

 and can certainly be regarded as a comparatively recent 

 acquisition. They become emphasized in the adult while 

 otherwise the head and under surface develop more brightly 

 into greenish yellow, the feathers of the back becoming 

 black with, however, bright green edges, giving a scalloped 

 appearance. 



It is noteworthy that Tasmania is the home of this form. 

 On the mainland two species seem to have evolved indepen- 

 dently : flaveohis {V\. III. fig. 3) has retained the coloration 

 throughout, but has brightened on the under surface to pale 

 yellow, and also the upper surface to the same colour, 

 retaining the black bases to the back feathers. The upper 

 surface of the tail has, however, become blue. The other 

 species, elegans (fig. 2), has in the juvenile stage evolved a 

 reddish cap, and the breast and vent have also attained that 

 colour, the belly remaining greenish. The mature, however, 

 has become a scarlet bird, the whole of the upper and under 

 surfaces being that colour, though the bases of the back- 

 feathers are black, while the upper surface of the tail is 

 blue. The scarlet coloration is much deeper at the limits of 

 its range, but in one district the scarlet has become orange 

 and the bird has been confused with the preceding species. 



The fourth species, icterotis (PI. III. fig. 7), when immature 

 recalls that of caledonicus, but has no red forehead, and the 

 cheeks are yellowish not bluish. This species develops yellow 

 cheeks, all the preceding species having blue cheeks, while it 

 also acquires a red under surface. As regards the upper 

 surface two phases are in being, one in which green still 



