THE BIRDS OF AUSTRALIA. 
it was described by VieiUot from a specimen probably procured by Flinders’s 
contemporary Baudin. 
The specimen preserved by Robert Brown stiU exists in the British 
Museum. 
It wiU thus be seen that, though met with by EUis in 1777 and by Brown 
in 1801-2, it was not described until 1818 and then by the French ornithologist 
VieiUot. This seems most peculiar, as it is such a distinct species. 
The most interesting feature of this species is its peculiar tendency ta 
melanism, and we would seem to see here an alteration, in a species already 
fixed, towards a black form. 
Thus the young of this species is very similar in coloration to that of 
C. hiaiicula, having the grey upper-coloration and pure white under-coloration 
of that species. The adult however has the whole of the head and throat 
black, whereas the species C. Tiiaticula has a white forehead and throat, a black 
band across the top of the head, and the rest of the head grey. A comparison 
at once suggests descent of C. cucullatus from an ancestor of C. Tiiaticula, and 
that the black head and throat has been produced through isolation in the 
southern parts of Australia. It is rare however that we see the melanistic 
tendency in progress, but my examples show that the forces which apparently 
fixed the black head and throat are stiU at work, and that this species wiU 
later have the whole of the back black as weU. 
Moreover though this melanistic tendency is most marked in Western 
examples it is also sometimes seen in Eastern specimens. 
Thus in most birds from the West the feathers of the back are mixed 
with odd black ones ; sometimes the scapulars are all black ; also the upper 
wing-coverts show odd black feathers ; in the specimen from Torbay, 
hereafter noted, the upper-back is whoUy black, the middle-back is black with 
some brown (not grey) feathers mixed, the lower-back is almost whoUy black, 
the scapulars are brown-and-black, while the upper wing-coverts and tertials 
are showing black fringes. 
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