BLACK-BREASTED BUZZARD. 
alike in colouring, but present the usual difference in size, the male being 
the smallest.” His description referred to the black-breasted bird. 
However, North has explained {Austr. Mus. Spec. Cat, No. 1, p. 244, 
issued October 31, 1911) : “ No one so far as I have observed has made 
any reference to the wide variation in colour of the adults of this species. 
Some specimens obtained in the same district are as different in colour as 
the light and dark varieties of the Wedge-tailed Eagle {Uroaetus audax), only 
in this instance age has apparently nothing to do with this distinction. Of 
two adult females now before me, both shot at the nest by the late 
Mr. K. H. Bennett, respectively in October and November in the Central 
District of New South Wales, the former agrees very well with the above 
description (of a black-breasted male), but the latter varies in the following 
respects. All the feathers on the upper parts are margined with rufous, 
the inner series of the upper wing-coverts are pale tawny fulvous, as are 
also the feathers on the head and nape, their bases whitish, those on the 
fore-head and hind neck only having blackish central streaks : all the under- 
surface creamy fulvous washed with rufous, except on the flanks and 
thighs, most of the feathers on the foreneck and upper breast having blackish- 
brown central streaks, and several of those on the middle of the lower 
breast broadly centred with brown near the shaft of the inner web 
only. The abraded quills and tail-feathers, and being shot while nesting, 
conclusively prove that this difference in colour is not the result of 
immaturity. Wing 18.2 inches. An adult male procmed in Western 
Australia is just the reverse, being blackish above and below, with 
scarcely a trace of rufous on the feathers of the upper parts, the upper 
wing-coverts and the nape and hind-neck being brown, some of the 
feathers having darker centres and whitish edges. Wing 18 inches.” 
Dr. Macgillivray, as quoted above, gives his experience as the female 
being black breasted and very much larger than the male, which did not 
have the black breast. 
The pairs in my collection, as recorded above, are almost exactly the 
same size and the same colour. 
I have concluded that only senile birds achieve the black breast, and 
in view of the disparity in size owing to sex and age, I at the present time 
cannot consider any subspecies of this species valid. 
As previously noted, the systematic position of the bird is quite uncertain ; 
however, owing to its peculiarities, I feel quite confident that it must have 
arrived in Australia with the first migration from the North. Kaup separated 
this bird as a subgenus of Milvus, noting : “ Bill twice as long as high : tarsus, 
upper-half transverse scales, lower half fine little scales : tail not forked.” I 
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