THE BIEDS OF AUSTRALIA. 
In my “List” I maintained the Northern Territory birds as a distinct 
species from the Queensland ones, but here I consider them conspecific. 
They are similar in size and markings hut not in coloration, although the 
immature of the Queensland and New Guinea birds agree with specimens 
from the Northern Territory in the narrow bars on the under-surface and light 
coloration. The mature of the Queensland form shows a darker upper- 
surface and the bars of the under-surface darker and wider. New Guinea 
birds have been examined showing the change, and it may be that Northern 
Territory birds will come to hand proving the same plumage change. At 
the present time there can be no doubt that N. humeralis and queenslandica 
are only subspecifically separable, and the differences observed between these 
and Tufa seem only due to age. The matter of size between the Northern 
Territory and Queensland birds, mentioned by Hartert, does not appear to 
be confirmed, whereas the New Guinea birds are less, as De Vis observed but 
did not emphasize : the paler coloration he mentioned is undoubtedly due to 
age. There seems to be doubt that this pale coloration is carried for some 
time, as a number of birds are met with in this stage, and that it may be 
some years before the dark plumage is attained. I have described and figured 
the Northern Territory and Queensland birds, which I now rank as subspecies, 
but I have never seen a specimen from either North-west Australia or Northern 
Territory as dark as the Queensland bird figured. 
Three subspecies may be recognised : 
RTidbdoglaux rufa rufa (Gould). 
Northern Territory, North-west Australia. 
Rhdbdoglaux rufa queenslandica (Mathews). 
North Queensland. 
This would appear to be a darker race, but there does not seem to be 
any appreciable difference in size. 
Rhdbdoglaux rufa humeralis (Bonaparte). 
New Guinea. 
This race may be slightly less and perhaps paler. Hartert, as quoted 
previously, considered it to be darker, and when Rothschild and Hartert 
wrote on Papuan Owls they did not further discuss it. 
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