82 British Diving Ducks 
lead-black with bone-coloured nail ; irides, dark grey ; front of legs and toes, greenish 
yellow ; webs, dusky black. 
Three nestlings hatched by Mr. Blaauw at Gooilust in Holland on June 26, 1908, 
began to show feathers on the scapulars on July i8th. On August 8th they were 
completely feathered except for the flight feathers, which were just beginning to grow. 
At this date the irides were chocolate-brown and the legs and toes yellowish. On 
August 25th the young birds were able to fly. 
Young Male. — In first plumage in September the young male has the head and neck, 
as far as the hind neck and throat, a dark brown ; the fore neck and side of the mantle are 
grey edged with white ; mantle and scapulars brownish black suffused with grey ; wing 
coverts darker, becoming pure black when they join the secondaries, which are white ; wings 
blackish brown, edged with white on the median coverts ; secondary coverts white in the 
centre, with black tips flanked with black feathers ; bastard wing and primary coverts and 
primaries black ; lower back and tail-coverts black ; tail dark brown with a grey suffusion ; 
flanks brownish grey; breast and belly white, becoming greyish brown on the thighs. 
Feet and legs similar to adult male, but less bright ; bill dull slatey blue. The young male 
is easily distinguished from the female by its superior size. The bill and legs are much 
larger, and there is no pale yellow bill-spot. The general colour, too, is much darker. 
The young male grows rapidly in size between September and December, and at the 
age of five months it is generally as large as the adult male. At this time a number of 
black feathers appear on the cheeks, and the neck collar of white is more or less complete. 
Individuals, however, vary considerably in December as to the amount of white which now 
comes in on the lores. In some the white patch is clearly defined, intermixed with brown 
feathers, in others these white patches hardly show at all {vide illustrations). Nearly all 
specimens at this season show ribbed or mottled scapulars, the blackish brown feathers being 
either edged with white or marbled, generally the former. The secondary coverts of the 
wings for the most part have now lost their black spots, though in some cases these are 
retained until the following July wing moult. The brownish flank feathers are well 
edged with white or grey. 
Rapid changes proceed in the plumage of the young male throughout January, 
February, and March, owing to the incursion of new feathers. The wings, back, tail, and 
flanks do not alter, but large numbers of feathers similar to the adult male (or conl- 
plete in colour) now make their appearance. The white lores patch does not alter much, 
being still intermixed with dark feathers. The scapulars, however, gain many of the white 
feathers with outer line of black, and the nape and brown head become almost black, 
the breast and belly a purer white. So the influx of new plumage continues slowly until 
May and June, when the white patch on the lores becomes pure white, and the whole bird 
has an appearance somewhat similar to the adult male, except that the head always remains 
faded and brown on the crown, and with patches of old brown feathers on the cheeks 
and chin. The scapulars are only half white, and the wings in the original immature 
state. 
In July the young male commences to pass into eclipse or semi-eclipse plumage, and 
whilst in this state can scarcely be recognised from the adult male except that the wings are 
not moulted as soon as those of the adult, nor do they resemble them as yet. In September 
