THE BIRDS OF AUSTRALIA. 
dates of arrival and departure. Now they are feeding on the narrow plain 
between the scrub and the mangroves, usual] y in flocks, and mix freely with 
Lalage tricolor and Artarnus cinereus, which frequent the same plain. . . . 
Up to the 28th May, 1911, at Marngle Creek these birds were numerous, and 
the number seemed to increase rapidly so that it became by far the commonest 
bird here. On the way over to Mungi Rock Hole, Jegurra Creek, these birds 
were in great numbers and at Mungi itself were numerous. On June 29, 1911, 
they were still in great numbers, but no male in adult plumage was seen until 
July 7, when one came in with a large flock of these birds to drink at a dam 
near Knowla Downs, Homestead, this being the only one seen to this date, 
be., Aug. 1, 1911, at this dam many hundreds of these birds came to drink 
every morning at about 8 a.m. On the 8th and 9th July whilst travelling 
down Jegurra Creek I saw thousands of these birds, but on the Fitzroy there 
were very few. I spent several days travelling down the river at a very few 
miles per day, so am certain the birds had left. Whilst at Derby from the 
25th to 31st July there were only a few stragglers. Numerous in May 1909 
in the Wyndham district. This is the common Chat of this district but is 
quite an irregular migrant. I have also seen the Ephthianura aurifrons, but 
they have only been noted in two seasons and then only in very small flocks 
up to six or seven birds.” 
Berney, writing from North Queensland, stated : “ The Tricoloured 
Bush-Chad is undoubtedly, I think, a migratory bird, but it is hard to distin- 
guish its movements. It is in the district all the year round, but much more 
numerous in the winter, the influx commencing during March.” 
Soderberg has written an interesting account which may be reproduced 
here, as it should prove suggestive in connection with colour changes in other 
species : “ Moulting. These specimens, adult and ju venal birds, were all 
in strong moulting. A comprehending of the observations shows an instance 
more of the kind of moulting which is described concerning the species Lalage 
tricolor indistincta. The red colour, just about to be developed, is obtained 
by partial colouring of the feathers. There are thus birds both with the change 
of plumage at very different stages and with very different development of 
the partial colouring of the feathers. Total colouring (red feathers in sheaths) 
is also seen. The juvenal, however, does not get all the feathers totally 
coloured in the first moulting. Some of them grow out and seem to remain 
with only a sprinlding of red, while others become entirely red, and others 
again lack every trace of it. Consequently we have the following cases : 
1. The red colour is present as edgings at the point of the pale yellow-brown 
feather. 2. The red colour is found as spots, sprinkled in the pale yellow- 
brown part of the feather. 3. The feather is totally coloured (red). Birds 
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