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Dr. A. G. Butler,



would be difficult to explain why all the birds of the same

species when kept together and similarly fed, should not be

similarly affected. It has indeed been asserted (and for some

years I believed the assertion), that a Bullfinch, if fed largely

upon hemp, would become black; but on my speaking to a

judge at one of our large shows as to the right of a black Bull¬

finch to a prize in the class for rare-feathered birds, he assured

me that hemp had nothing to do with the colour ; and when I

reflected that I had once been cautioned against giving hemp to

Cardinals, because it dulls the colouring,” an assertion which

I had amply disproved by invariably giving it to several

species for many years, I was convinced that hemp did not

necessarily affect the colour of Bullfinches.


If melanism w r ere due to unnatural conditions apart from

vigour of constitution, albinism might also be the result of

artificial conditions apart from delicacy of constitution ; but, in

that case, it should surely have a similar effect upon all members

of a species.


I think it will be admitted that, as examples of vigorous

aviary birds, the Java Sparrow and the Martinican Dove rank

fairly high. At the approach of the breeding-season the vitality

of birds should certainly be at its highest; just as, at the

moulting-season it is most heavily taxed. Now, we know that

when ready to breed, male birds are very aggressive, and think

nothing of plucking out one another’s feathers : when these are

replaced, the bird being in its fullest vigour, they should be

expected to be more full of colour than if produced after an

ordinary moult; is this the case? When Java Sparrows fight

they attack their antagonists’ heads, and the white cheeks being

most conspicuous are sometimes wholly denuded of feathers :

when this occurs the feathers are subsequently replaced, but are

wholly black instead of white (Vide Bartlett, “Monograph of

the Weaver-birds, etc.,” plate II. of Munia oryzivora ): I have a

skin of this variety produced in my bird-room, and the late

Mr. Abrahams assured me that he had seen other examples all

produced in the same manner. In the case of the Java-Sparrow,

however, if the bird survives until the next moult, the white

cheeks are renewed, the reproductive energy not being then



