ARCTIC TERN.
STERNA MACRURA, Naum.
Sterna macrura, Naum. Isis, 1819, p. 1817; Naum. x. p. 114;
Yarr. ed. 4, iii. p. 553.
Sterna arctica, Macg. v. p. 643; Heivitson, ii. p. 481.
Sterna hirundo, Dresser, viii. p. 255.
Nordische See-Schwalbe, German.
As this is a species with which I have virtually no
personal acquaintance, except in cabinets and glass-cases,
I will only say that it is the most abundant species of its
family throughout the northern portions of the British
Islands, and, in fact, of those of Europe in general. It
is, however, by no means strictly confined to the extreme
north, and breeds on many of the islands off the south
and west coast of Ireland. In food and habits this bird
is said hardly to vary from the Common Tern. In adult
plumage the Arctic may always be distinguished from
the Common Tern by its dark grey underparts, longer
tail-feathers, wholly red bill, and very short tarsi, whilst
the immature birds may, according to Mr. H. Saunders,
be always recognized by the narrowness of the dark
line that runs along the shaft on the inner webs of the
primaries. This line is both darker and more extensive
in the Common Tern. The range of this species extends
from "as far north as human foot has trodden" to
Brazil, Peru, and Table Bay.