COLYMBIDJE. 541 



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 



3 A 



