are in an evident state of change, some of them being quite
as black and the spots on them as purely white and distinct
as in the summer-dress; the rest of the feathers black
towards the base, margined with dullish-grey; the places
where the white spots either have been or will he, are distinctly
marked ; the rump, tail-coverts, tail, and hack of the
thighs are not so much in a state of change, being black
with small white spots as they are in the breeding-dress.
A specimen shot on the 19tli of December was still more
advanced towards the nuptial garb about the head and throat.
A young male, nearly full grown, killed in the winter, has
the beak of a brownish-white horn-colour; irides reddish-
brown ; head, back of the neck, and all the upper surface of
the body greyisli-hlack; all the feathers on the hack broadly
edged with ash-grey; chin, neck in front, and all the under
surface of the body dull white ; outer surface of the legs
and toes dark greenish-brown ; edges and inner surface
lighter greenish-brown ; the whole length thirty-one inches;
of the wing thirteen inches and a half.
The nestling is covered with a stiff down, sooty-black on
the upper parts, paler on the throat, and greyish on the
abdomen.
The figure below represents the form of the foot in this
genus of birds.
PYGOPODES. CO L YM BIDJi.
COLYMBUS ARCTICUS, LillUffiUS.*
THE BLACK-THROATED DIVER.
Colymbus arcticus.
Op the three species of the genus Colymbus known in
England, the Black-throated Diver is the most rare, occurring
but seldom on the southern shores. Young birds
have been taken in winter in Cornwall and Devonshire, but
Mr. Gatcombe says that he has never seen an adult obtained
* Syst. Nat. Ed. 12, i. p. 221 (1766).
VOL. IV. P