THE VICTORIAN NATURALIST. 171 



NOTES ON SOME ABNORMAL-PLUMAGED BIRDS. 

 By Robert Hall. 



{Read 'before the Field Naturalists' Club of Victoria, 13th Nov., 1899.) 



Deviations from the normal plumage of our native birds have 

 seldom been brought before our society, and, as far as I know, 

 few papers have been published in Australia on the subject. 

 Some years ago, however, Sir Walter BuUer contributed a paper 

 to the " Proceedings of the New Zealand Institute " on " Albino 

 and Semi-Albino Birds." I therefore think it would be of service 

 to collectors to place on record brief descriptions of some varia- 

 tions which have come under my notice, and if other members 

 would from time to time do the same an interesting series of 

 observations would be recorded. 



" Albinos are notoriously shy," says Professor Alfred Newton, 

 meaning that they are very uncommon, and so they surely are 

 when we compare the number of those known with Mr. A. R. 

 Wallace's estimate of the number of individuals of any one species. 

 In his work " Darwinism," Mr. Wallace speaks of any very rare 

 species numbering, in all probability, 30,000 or more, while a 

 common species will number 30,000,000 or even 300,000,000 of 

 individuals. Just imagine 30,000 birds of the Atrichia, and the 

 egg of the western form still a desideratum in our colonial 

 museums. 



Sir Walter Buller is particularly struck with the inherent 

 tendency to albinism in his colony, and refers to it as one of 

 the distinguishing features of the New Zealand avi-fauna, while in 

 India the inherent tendency is in the opposite direction, melanism 

 being frequent. Melanism has been noted in many American 

 and European birds, both passerine and grallaceous. 



As regards Australia, I should be inclined to say that in the 

 south the tendency is to albinism, while in the north it is to 

 melanism, and as an example I would call to mind a variety of 

 the parrot Platycercus elegans {^^ennaiitii), known to us as P. 

 nigrescens, found in Queensland, which is, doubtless, the black 

 form of the southern bird, which in its turn is known to assume 

 abnormal dress. 



In the introduction to the second edition of " Buller's Birds of 

 New Zealand," page xlii., and in the " Transactions of the New 

 Zealand Institute," vol. xxvii. (1894), page 135, forty species of 

 birds are described with abnormal plumage, and a glance at the 

 lists will show that birds of prey, both diurnal and nocturnal, 

 insect-eaters, semi-vegetarians, freshwater and sea birds have all 

 erred. In passing, I may mention that the British Museum 

 authorities have noted some 56 specimens of the parrot family 

 which are not identical with recognized species, and have regarded 

 them as accidental varieties. 



