tering
as far south as Long Island.

This bird differs from the Glaucous-winged only in the pattern of the
gray markings of the primaries and in having a little lighter mantle. It
is quite common in its breeding haunts where it places its nest high up
on the ledges of the cliffs. The eggs are not different apparently from
glaucescens.

46. NELSON'S GULL. _Larus nelsoni_.

Range.--Coast of Alaska.

Plumage exactly like that of Kumlien Gull and questionably a new
species. The nests and eggs are not to be distinguished from the
preceding.

[Illustration 044: Iceland Gull. Glaucous-winged Gull.]
[Illustration: Pale greenish brown.]
[Illustration: left hand margin.]

Page 43

47. GREAT BLACK-BACKED GULL. _Larus marinus_.

Range.--North Atlantic on both the American and European sides; breeds
from Nova Scotia northward and winters south to the Great Lakes and the
Middle States.

The largest of the Gulls (thirty inches long) and unlike any other. The
mantle is dark slaty black, and the primaries are black with white tips.
The bill is very large and powerful and quite strongly hooked. They are
quite abundant birds in their range, and are very quarrelsome, both
among themselves and other species. They do not breed in as large
colonies as do the other Gulls, half a dozen pairs appropriating a small
island to the exclusion of all other birds. They are very rapacious
birds and live to a great extent, especially during the breeding season,
upon the eggs and young of other birds such as Ducks, Murres and smaller
Gulls. They place their nests upon the higher portions of sandy islands.
They are made of grasses and seaweed. The three eggs are laid early in
June; they are grayish or brownish, spotted with brown and lilac. Size
3.00 x 2.15. Data.--South Labrador, June 21, 1884. Three eggs. Nest on a
small island off the coast; of grasses and moss.

48. SLATY-BACKED GULL.--_Larus schistisagus_.

Range.--North Pacific and Arctic Oceans.

This Gull, which is similar to the Great Black-backed, but is smaller
and has a lighter mantle, does not breed in any considerable numbers on
the American side of the Pacific. It nests in June on some of the
islands in Bering Sea and probably more commonly farther north. They
often nest in company with other species, placing their small mounds of
seaweed on the ground on the higher parts of the islands. The full set
contains three eggs of grayish or brownish color, spotted with dark
br