^°190S^^] General Notes. 227 



that it was taken as an abandoned nestling some four years previous and 

 kept in a large cage hung in a kitchen and fed on a diet of ground hemp, 

 grated carrot and cornmeal varied by an occasional small bit of apple, a 

 minute quantity of scraped raw meat about once a week, and in spring 

 time occasional meals of angle wonns. Thirteen months ago last Novem- 

 ber the robin was moved from its original habitat to its present home where 

 it hangs in a large wire cage suspended about five feet from the floor in 

 front of a south window in a rather low kitchen. The room is not used for 

 wasliing, and but little cooking is said to be done in it, and its temperature 

 is said to be cool; but not unlikely it may be a little higher and more 

 humid than normal. 



Up to the latter part of last September, when its moult began, the robin 

 had been in rather bright, nonnal coloration which at once gave place to 

 the extreme melanistic phase that it had assumed aljout two weeks previous 

 to my seeing it, November 6. Again, on January 28, I called to see the 

 robin and found that the black pigmentation of the bill had ahnost entirely 

 disappeared and that it was bright yellow except for a dusky spot near the 

 tip of the culmen, a change that I was told had occurred within the preced- 

 ing four days. The eye-rings were then conspicuous, appearing whitish 

 at a distance but really greenish yellow. The tarsi and toes were decidedly 

 lighter, the pigment of the fonner seeming to have formed ill-defined spots. 

 About a week previous to this inspection white feathers were noticed by 

 the owner in several parts of the plimiage as the bird sat with erected 

 feathers after bathing. . I could see a number of these, imperfectly covered 

 by the black ones, and a faint indication of fine white streaking, probably 

 due to underlying white feathers, was seen on the breast. On February 

 10 I again viewed the robin and found the dusky spot on its culmen farther 

 reduced, and there were then apparently three or four white under tail 

 coverts. As the bird is. lively and attempts always to face an observer 

 it was impracticaljle to determine whether there was a farther increase in 

 the underlying white feathers of the body and neck. 



Coues ' mentions a black robin turning white, and Barrows ^ mentions 

 a robin "somewhat variegated with black and white, the black predomi- 

 nating above, though Mr. Leonard thinks the bird became ultimately 

 almost white." 



It appears that in the majority of black captive robins there has been a 

 succeeding albinistic phase. 



As melanism is due to an abnormal increase in black pigment or mela- 

 nin it seems but natural to suppose that a more or less lengthy persistence 

 of such a condition would produce an exhaustion of the supply and of the 

 ability to renew it which would result in albinism more or less complete, 

 depending on the degree of exhaustion. There is, I believe, little data to 

 support such a theory and it would have to be obtained experimentally 



1 Coues, Elliott, Bull. Nutt. Ornith. Club, Vol. Ill, p. 48. 

 2 Barrows, Walter B., Auk, Vol. II, p. 303. 



