Vol..X1V 
TBo9 Cuapspourne, Spring Plumage of the Bobolink. 143 
The buff edging of the breast feathers was never more than a 
narrow line, evidently owing to the absence of the long fugacious 
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.’ 
The dealer from whom I bought the bird told me, that “last 
fall he (the Bobolink) lost lots of feathers”; and added: “ In 
spring Bobolinks don’t often lose any feathers to speak of. 
Sometimes I don’t believe they lose any feathers at all; and you 
can’t see any pin-feathers either while they are getting black. 
But in autumn the pin-feathers stick out all over them. Once in 
a while though, I’ve seen one have a regular moult, just as they 
do in fall.’ The above was written verbatim at the time, and is 
further proof that because one individual of a given species has 
‘ moulted, it does not necessarily follow that all individuals of that 
species ‘moult’ also. 
Turning next to the series of skins :— The only early spring 
material is from Corumb4, Brazil. The male already referred to 
(Coll. Amer. Mus. Nat. Hist., No. 32783;) taken March 1, shows 
new feather-growth in a marked degree ; and as was pointed out 
by Mr. Chapman, ‘ moulting’ was in full progress. It is however 
quite another matter to prove that no color-change was also going 
on simultaneously in any of the feathers; for ‘hough without the 
loss of old feathers from the tracts concerned, — or in other words, im 
the absence of ‘ moulting,’ — an alteration in color must be due toa 
color-change in the same feathers ; yet it does NoT follow, on the other 
hand, that because a bird is * moulting,’ a color-change in the individ- 
ual feathers — be they old or new — ts thereby excluded. In fact the 
Corumbé bird itself furnishes conclusive proof that just the 
reverse is the case; and on careful examination one finds here 
IRE SOE i Rr eee ee Ne ane 
the Corumbd specimen, and Dr. Allen says nothing of any similar coloring 
among the birds seen by him. When we call to mind the fact, — to be referred 
to later, —that the black of the Bobolink is really due to brown, instead of 
black coloring matter, — it is at once clear that the excess of chestnut and white 
show a lack of the normal quantity of pigmented matter ; and it seems almost 
sure that in the Corumba bird, we have not a normal example, but a partial 
albino! 
