714 BLACK-THROATED DIVER. 
The Black-throated Diver has been recorded as an exceptional 
visitor to the Feroes; while in winter it is met with on the 
coasts and inland waters of the Continent down to the Mediter- 
ranean, Black and Caspian Seas. In summer it is decidedly rare 
as a breeding-species to the southward of the German side of the 
Baltic, but northward and eastward it is very abundant on the lakes 
of Scandinavia, Finland and Russia ; while, by way of Kolguev and 
the south island of Novaya Zemlya, it can be traced across Siberia 
to the Pacific. In winter it visits Japan. Arctic America, especially 
to the west of the line of the Rocky Mountains, is inhabited by a 
form with a paler nape; but our bird seems to occur over the eastern 
area. It has not yet been identified in Greenland, Iceland, Jan 
Mayen or Spitsbergen. 
In Scotland the margin of a green island in some fairly large 
fresh-water loch is usually selected; the 2 eggs being laid in May, 
often on a substantial mass of crushed vegetable matter ; they vary 
in colour from olive- to russet-brown, with sparse spots of black or 
umber: measurements 3°25 by 2°15 in. In the Petchora district 
Messrs. Harvie-Brown and Seebohm found a large floating nest, 
partially supported by aquatic plants. Mr. S. Graham informs me 
that he knows a mountain-loch in Argyll where, on three occasions, 
the first and second clutches of eggs were taken, after which a third 
clutch was produced and hatched. Incubation lasts 28 days (W. 
Evans). The cry of this Diver is loud and discordant, the flight is 
said to be unusually rapid, and the food consists chiefly of fish. 
The adult in summer has the crown and hind-neck ash-grey ; 
upper-parts nearly black, barred and spotted with white; chin and 
throat purplish-black, with an intermediate half-collar of short white 
streaks ; sides of the neck striped with black and white ; under-parts 
white ; bill black ; irides red ; legs and feet brown. Length about 
27in.; wing 11°75in. Females are but slightly smaller than males, 
and both sexes, when mature, have black throats. By the middle 
of September the autumnal moult is completed, and the chin, 
throat, and under-parts are then white, while the upper plumage is 
chiefly ash-brown. The young bird has the hind-neck of a much 
purer grey than the immature Northern Diver, which it otherwise 
resembles in its general plumage ; it is, however, decidedly smaller. 
