COLYMBIDZ. o4l 
full adult plumage or a mature bird changing sum- 
mer for winter plumage : though this would generally 
be about the end of the moulting season, this bird 
does not appear to be changing its feathers by moult, 
but only the colours of the feathers themselves: 
the bill is black, mixed with a little flesh-colour 
(now white) towards the base; the top of the head 
and back of the neck are black ; the lower part of the 
face to the eyes, the chin and throat white; the black 
encroaches on the white towards the bottom of the 
throat, nearly joining in front at that place; the 
back and scapulars are in an evident state of change, 
some of the feathers being quite as black, and the 
white spots on them quite as pure and distinct, as in 
the bird last described—the rest of the feathers black 
towards the base, margined with dullish grey, the 
places where the white spots either have been or will 
be is distinctly marked, and is much the same colour 
as the margin; the rump, tail-coverts, tail and back 
of the thighs are not so much in a state of change, 
being black, with small white spots, like those parts 
of the last-mentioned bird; a few of the black and 
white streaks appear in places on the sides of the 
breast, the rest of that part being mottled dusky and 
white, mostly white; the under parts white. This 
appears to me rather an interesting specimen, as 
showing the peculiar change of plumage, and also 
from the time of year it was taking place. A speci- 
men recently sent from Barnstaple, killed on the 
BA 
