62



Colour change in the plumage of birds.



place. In passing, I might mention that one of my specimens of

T. emini has two tail feathers crimson like the colour on the wings!


My birds are always bathing !


Now as regards colour change in Pyromelana. I have a large

series of four different species, showing all stages of plumage, and it

is a noticeable fact that those which appear to bear evfdence support¬

ing Dr. Butler’s statement are either—


(1) Young males changing into the breeding plumage for

the first time.


(2) Males which are obviously out of condition, and which

have not sufficient vitality in the colour glands to produce the

change.


(3) Males changing normally, i. e. red feathers are red.

Quills present!


Males of class 1 show feathers in quill which are either red,

orange or yellow, indicating a moult. Class 2 includes males with

bills far from black (though they were breeding-birds), and also with

feathers in quill practically over the whole of the body—some red,

some orange—other indications of reduced vitality being the retention

of very old worn feathers which the birds have not been able to throw

off. I refer above to birds shot in the field.


I have a large numher of captive birds in my aviaries (outdoor

and indoor, i. e. on verandahs), and these when taken up and

examined corroborate my statements above.


I have before me Dr. Butler’s note on the same subject in the

‘ Ibis ’ of July, 1916, p. 476. Dr. Butler admits that the bird under

discussion commenced its “ change ” rather late ; further, that it died.

One can only presume that it was ailing without actually showing it

to a marked extent, the moulting taking place slowly but not

normally, and then it died.


Dr. Butler states also that when the change takes place no

moulted feathers are found ! Do the birds not eat them ? Many of

mine do ! I give this evidence for what it is worth. I cannot at

present admit Dr. Butler’s view, but I am still open to conviction on

sufficient evidence.



