150 
Stray Feathers 
The Emu 
L 1st Oct. 
Is There any Reasonable Limit to the Ability or the Intelli¬ 
gence of Australia’s Bower-birds? —It is not to be wondered at, 
perhaps, that the mating impulse causes birds generally to display 
considerable skill in making nests for their eggs and young; 
but what is to be said of birds which, quite independently of 
that primal impulse, and with the beak alone, wedge sticks and 
grasses into playhouses in a fashion that would severely tax 
the skill of ten human fingers? And now we have to credit 
a Bower-bird with being not only a house-builder, but a house- 
painter. Whether this painting business is at all general seems 
doubtful. I have examined many bowers of the Satin-bird, 
but had no evidence of it until recently, when it was brought 
to notice by Mr. E. Nubling, R.A.O.U., of Sydney, and sup¬ 
ported by a bushman, who told me he noted the same thing in 
a South Coast district many years ago. In one bower, observed 
by Mr. Nubling in the National Park, the whole of the inside 
wall was painted. That is to say, the aesthetic-minded bird 
had secured a vegetable dye of some kind, carried it to the 
bower, and laboriously blackened every one of those hundreds of 
sticks, from top to bottom. The dye, drying flat, resembled soot 
or the aftermath of fire, and superficial observation would have 
suggested that the sticks were burnt, had it not been that only 
the inside of the walls was thus treated. We saw some of this 
black substance in two bowers on Sunday last, but by that time 
rain had washed off the greater part of the curious decoration. 
*—A. H. Chisholm, C.F.A.O.U., in Sydney Daily Telegraph. 
* * * 
Breeding Plumage of Birds.—At the recent congress of 
the R.A.O.U., in Hobart, the question was asked, “Was the 
nuptial dress acquired only at the moult, or did the bird’s 
feathers change in colour at the breeding season ?” The opinion 
was expressed that, though the change did, as a rule, occur 
at the moult, nevertheless feathers sometimes become brighter 
in hue owing to the stimulus of the breeding season. The 
latter idea seemed to me untenable for physiological reasons, 
but, being by no means sure of my ground, I refrained from 
comment. It would seem, however, fully grown feathers being 
dead things, having no organic connection with the bird, and 
having the nutritive pulp capsules dry and empty, cannot be 
in any way influenced by the vital processes of the animal. 
Apart, therefore, from such things as the rubbing off of dull 
edges exposing brighter colours beneath, as in the black throat 
of a ^ House Sparrow, and such things as extra care in 
preening, etc., I am inclined to think that no change in the 
colour of mature feathers ever takes place. In this connection 
the writer of the article in The Encyclopedia Brittanica says:— 
“According to some authorities, however, some birds acquire a 
change of colour without the moult by ascent of pigment from 
the base of the . feather. The Black head assumed by 
many Gulls, in, spring, is, for example, said to be gained in 
