possible that a few pairs breed on some of the numerous
lakes of the remote districts of Donegal.
The Red-tliroated Diver breeds in the Faeroes, Iceland,
and Spitsbergen, and to the north of the latter Parry found
it as far as he went on his boat-voyage. It is abundant in
Norway and Sweden, especially to the north of the Arctic
circle, occurring in summer, according to Mr. Collett, on
almost every holm and islet where a sheet of water is to be
found, though but a few square yards in extent. It is
numerous in the northern parts of Russia ; breeds on Novaya
Zemlya ; and is generally distributed throughout Arctic
Siberia to the Pacific ; ranging southwards in winter to
Japan, China, and Formosa. It is found across Arctic and
sub-Arctic America, migrating as far south as Maryland in
winter. In Europe its migrations extend to the Mediterranean,
the Black Sea, and the Caspian; and it is occasionally
observed on inland waters, but less frequently than its
congeners. Yon Heuglin says that he has seen immature
birds on the lagoons of Lower Egypt.
On the subject of migration Mr. Gatke, of Heligoland,
writes under date of the 22nd of December, 1879 :—
“ Colymbus septentrionalis, almost by the million ; during
the last forty years there have never, during a single autumn,
been a fiftieth part of what we see now every day—all passing
along, principally during the forenoon, east of island in
an E. by N. direction, which I think they continue till
coming to the Holstein coast, then strike off in a northerly
course up to the extreme north of Jutland, and from thence
cross over to the Dutch coast, perhaps next morning to renew
the trip. There are constantly so many that one scarcely
can believe them always to be fresh birds” (Migration Report,
Zool. 1880, p. 184).
The Red-throated Diver frequents more retired spots than
the Black-throated species, and prefers the shores of small
tarns or even pools—often at a considerable elevation—to
the islands of a larger loch. Sometimes there is a slight
nest of loose rushes and dried grass, but more frequently
the eggs are laid upon the bare turf, or stones, within a few
feet of the water’s edge. In Scotland laying commences by
the middle of May, but fresh eggs may be found a month
later ; they are two in number, of a deep greenish-brown or
brownish-grey, spotted with umber; average measurements
2*75 by 1*8 in. It is rare for more than a single pair to
breed on the shores of the same lake ; but Mr. Collett cites
a remarkable exception to the rule, for on a small tarn on
an island in the Porsanger Fjord, West Finmark, on the 3rd
of July, 1872, he discovered along the banks, in the space of
half an hour, no less than fifteen nests, each containing two
eggs, most of them in an advanced stage of incubation. A
male sitting on the eggs of his mate was shot on the 30th
of June, from which it appears that the sexes divide their
duties. During the breeding-season, while on the wing,
they utter frequently a sound like the word kakera, kakera,
by which name they are called in many parts of Scandinavia.
Its food consists of fish, molluscs, and crustaceans. In
its progress under wrater this species employs its wings as
in the act of flying. In diving, both this species and its
congeners slightly sink the body, and then, bending the
head and neck forward, disappear with a gentle plunge,
which scarcely leaves a ripple on the surface of the water.
When suddenly disturbed or frightened, a splash is, however,
inevitable.
In the adult bird the beak is of a bluish horn-colour;
the irides red ; the front and top of the head, chin, cheeks,
and sides of the neck ash-grey, varied with lighter grey
lines and spots; back of the neck almost black, with short
longitudinal lines of white ; the scapulars, wing-coverts,
back and upper tail-coverts nearly black, speckled with
white; quill-primaries black, without spots or streaks ; on
the throat the red colour forms a conical patch, the point
of which is directed upwards, the base resting on the breast,
which is white; all the under surface of the body white ;
flanks spotted greyish-black; legs, toes, and their membranes
dark brown on one surface, pale wood-brown on the
other.
Male birds measure twenty-four inches in length, and