16 Zoologia: N. Y. Zoological Society. [Vol. I 



Melanism in cage-birds has received such desultory atten- 

 tion that as regards food, temperature and other environmental 

 conditions, we are as much at a loss for definite details as in the 

 case of wild birds. 



Elliot Coues, W. B. Barrows, Walter Faxon and others have 

 described melanistic American robins in captivity, some of which 

 were congenital in the character of their abnormal coloration, 

 while in other cases the dark plumage was assumed gradually 

 moult by moult. In one bird, the normal plumage appeared dur- 

 ing one moult, sandwiched in between melanistic moults, and 

 when examined after death, the bones of this bird were found to 

 contain only one-third of the normal amount of calcium phos- 

 phate. 



Another robin which became "as dark as a European black- 

 bird," was confined in an aviary built like a greenhouse and 

 sloping south, a condition which might indicate that the bird 

 lived in an atmosphere of considerable humidity. 



In an article on "Notes on Melanism and Albinism in Birds," 

 by Dr. A. G. Butler, the theory is advanced that melanochroism 

 in old age is the result of unusual constitutional vigor. He in- 

 stances a song thrush which had lived in captivity for sixteen 

 years and had become quite black. Elsewhere he says that among 

 thrushes and skylarks which have lived long in captivity melan- 

 ochroism is not uncommon. 



He does not believe that food has anything to do with 

 melanism in captive birds, even doubting whether there is any 

 truth in the oft-quoted case of darkening bullfinches by feeding 

 them upon hemp seed. On the other hand, Distant quotes from 

 Hasting's notes, that not only bullfinches but skylarks and other 

 birds become black when kept upon a diet of hemp. 



As a direct cause of local melanism in an individual bird, 

 Dr. Butler tells of a female Martinican dove, Zenaida aurita, 

 which had been persecuted by other birds until every feather 

 had been removed from the lower back, and w^hen, after removal 

 to a cage by itself, these feathers were renewed they all proved 

 to be perfectly black in hue. Renshaw was unsuccessful in re- 

 storing a nonpareil which had moulted yellow, to its normal col- 

 oring, by an increase of animal matter in the food. 



Among the weaver birds, Ploceiclae, some species are re- 

 ported to become frequently melanistic in captivity and Salvadori 

 observes that among doves, Chamaepelia talpacoti, when kept in 

 confinement, often becomes partially or wholly black. Besides 

 these there are many other records, all practically worthless on 

 account of the total lack of clear, definite details of conditions. 



