by their black and orange bills ; but, as already mentioned, the
particular species figured is, I think, arvensis and not the true
segetum, which is smaller, besides having much more black on
the bill. It may be that, as Uechstein says, the older and more
mature birds lose a good deal of the black on the bill, and so
become arvensis; but this is not Naumann's view, and Naumann,
who studied every species carefully in life, is rarely in error in
such matters.
