Seen | CHAPMAN, Spring Moult of the Bobolink. 153 
find a single new white feather in this or any part of the bird’s 
plumage. I do find, however, new black feathers appearing, and 
there is in my mind, no doubt but that in due time these yellowish 
white feathers of the fall plumage would have been replaced by 
the black ones of the spring plumage. 
And this brings me to Dr. Chadbourne’s statement that these 
white feathers and a “chestnut shading” are evidence of albin- 
ism in the Corumbé specimen, neither of them being shown in 
his cage-bird. As for the white feathers in the abdomen, allow- 
ing for a slight fading and abrasion due to their having been 
worn for a longer time, they are exactly like those found in 
the same part of several Reedbirds in the collection of the 
American Museum. In other words, they appear perfectly 
normal and are in no way albinistic. The “chestnut shading” 
mentioned by Dr. Chadbourne as an evidence of albinism in the 
Corumb4 bird, and as not shown by his cage-bird, I am unable 
to detect. In any event, it is obvious that the two birds are not 
comparable. With the exception of the white abdominal area the 
few old feathers remaining in the plumage of the Corumba bird 
do not materially effect its color, which is that of the newly 
grown feathers, while Dr. Chadbourne’s cage-bird was acquiring 
its spring dress not by moult, but by change of color in the old 
feathers. I think, therefore, that Dr. Chadbourne is mistaken 
when he states that the Corumba bird is “apparently a partial 
albino,” and I must again assert my belief that this bird is 
acquiring its breeding plumage by a comp/ete moult. 
Admitting this, it may be said that one moulting specimen does 
not prove that all wild Bobolinks moult in the spring, and, in 
replying to this objection, I am very glad to find that Dr. Chad- 
bourne and myself are in accord as to what constitutes evidence 
of spring moult in the Bobolink. Speaking of his cage-bird 
he says: “ The buff edging of the breast feathers was never more 
than a narrow line, evidently owing to the absence of the long 
fugaceous tips, which are so characteristic of the newly developed 
feathers, and it is therefore probable that spring males showing 
much buff suffusion beneath have recently passed through a 
‘spring moult,’ or at least through a partial feather change.” It 
is these tips which give the freshly moulted Corumb4 bird so 
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