THE BIRDS OF AUSTRALIA. 
from the tableland bird is found on the McArthur. I later got eggs of both 
forms.” 
Mr. Tom Carter’s notes read : “ In your 1912 4 List ’ the White-backed Magpie 
is given as occurring in Western Australia generally. My experience is that its 
northern limit may be said to be the Murchison River (about Lat. S. 28°) as far 
as the coastal region is concerned. The general course of the Murchison is 
from the N.N.E. to the S.S.W. (or roughly, N.E. to S.W.). At the distance of 
250 miles from the coast, the main Murchison River is, for some 150 miles, 
only fifty miles distant from the Gascoyne River, and the Gascoyne River is 
only about seventy miles south of the Ashburton River. Consequently, the 
head waters of these three large rivers are close together. Probably in times 
of flood, they actually join, by means of tributaries and flooded plains. In this 
region of the upper waters of these rivers, Gymnorhina tibicen longirostris takes 
the place of G. dorsalis. Mr. Milligan, when describing longirostris , does not 
give the exact locality on the Asburton River where the type specimens were 
obtained ; but as he also mentions birds, obtained about the same date, on' the 
Cane River, I take it that G. longirostris occurs also on the lower reaches of the 
Ashburton River, because the Cane River is a short one (about 100 miles) and 
enters the sea about 25 miles north of the Ashburton. Shortridge’s notes (Ibis, 
1909 p. 670) state : ‘ The Long-billed Magpie was not uncommon on the 
Gascoyne River.’ Apparently Mr. Shortridge’s specimens were obtained only 
at Clifton Downs Station, which is one hundred and twenty miles from the 
coast up the Gascoyne River. I have never been more than sixty miles up 
the Gascoyne, and that was many years ago (1888), but no Magpies of any sort 
were ever observed by me there or on the lower part of the river, which I know 
well and recently visited again in 1911 and 1913. It is quite possible that 
G. longirostris is extending its area lower down the river, as G. dorsalis 
undoubtedly extends its range, with increasing settlement, further south ; but 
I think Mr. Shortridge’s note should have read ‘ is not uncommon on the 
Upper Gascoyne River.’ I would now give a warning to future ornithologists 
in the above district that in recent years many of the squatters have brought 
caged birds of G. dorsalis from the south-west, and let them loose in the 
Gascoyne, Minilya River and other districts, so that in future years there will 
doubtless be hybrids between G. longirostris and G. dorsalis. When on the 
Minilya River, in 1913, I saw specimens of the latter species in the bush which 
Mr. McLeod told me he had set at liberty, and warned me against shooting any 
of them. Mr. J. Butcher of Boolathanna Station on the Lower Gascoyne did the 
same thing. G. longirostris, many years ago, was much esteemed by inland settlers 
as a cage bird, but they were difficult to obtain. Quite probably some cage 
birds have escaped or been set free and so extended the range of this species.” 
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