BIRDS OF THE AUSTRALASIAN SOUTH POLAR QUADRANT. 
nestling is somewhat variable. Two are almost always hatched in each nest; 
one is generally about twice the size of the other in the earlier stages of their 
existence. 
In the majority of the chickens the down is uniformly dark and sooty, 
which gives way before long to a smoky colour, which gets an old and dirty look 
by the time it begins to loosen on the under-surface of the flippers. This moult 
begins on the abdomen and the thighs, where the wdiite side stripes appear 
as the new feathers are disclosed; those parts being the first denuded sim ply 
because they bear the brunt of the wear and tear. Then it is shed from the 
face and head, round the bill, and round the tail. The upper breast and neck 
and back hold longest to the down, which will now be clogged with ice and 
dirt and snow, all of which are abundant in the rookery from time to time. 
The colour of the feet meanwhile has also been undergoing change. 
When first the chicks are hatched their feet are very dark, and in the 
youngest nestling we obtained they were a very dusky blackish-red. This 
rapidly alters for a clear bright red, which reaches its maximum in about 
three weeks and then gradually turns to pale flesh-colour on the dorsal, and 
black on the plantar surfaces and these are retained by the bird for life. 
The soles of the feet are imiformly black as a ride. The colour of the nails 
is blackish to begin with, but they gradually change in a couple of months to 
brown. The nails of the adult are long and brown on the upper-surface. 
Underneath they are darker and there is a surface mar kin g, which is due, 
apparent^, to the wearing of the nail, the deeper parts of which are of a 
different density to the surface layers. 
Returning now to the change of colouring which takes place at the finish 
of the first moult when the nestling down is shed, the first noticeable point 
is that the throat is white. The general colour of the upper part of the head, 
neck and back is bluish-black, with a sharp demarcation line dividing it from 
the pure white throat, fore-neck, breast and abdomen. The flippers are bluish- 
black above and white beneath, with blackish patches at the tips, which vary 
much in size and may be absent. The bill in the adult is brick-red with 
black on the tip and upper-surface of the upper mandible, while the lower 
is black upon the sides along the cutting edge. The eyelids in the nestling 
are black, and become white only at the second autumnal moult. In the 
immature plumage the suggestion of white eyelids at times by the habit the 
bird has of showing the white sclerotic above the coloured iris; in the adult 
this habit enhances the value of the pure white eyelids which are so 
characteristic. H the bird is watched when neither frightened nor excited 
the prominence of this white ring is much reduced and the upper lid is almost 
hidden under the black feathers of the brow. The colour of the iris varies 
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