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THE MASKED GULL. 
sometimes called, being deep brown instead of leaden blue. 
This is a common species ^vith lis ; it is generally distri- 
buted throughout the country, and is permanently resident, 
breeding in much the same places as the Common Gulls, 
and, like them, often going inland to feed on the worms and 
larva turned up by the plough. When shoals of young 
herrings, or other fish, appear on the coast, they congregate 
in vast numbers, along with Gulls of various speciesj and 
continue to feed upon them as long as they remain. A 
remarkable scene of this kind, which occurred in the Frith 
of Forth in the winter of 1839, is described by Mac- 
gillivray. 
The IMasked Gull is Yarrell's name for the next species, 
which is very rare with us. The dark shade does not 
extend over the whole of the bird, but simply from the 
occiput dowuAvard to the throat, leaving the back of the 
head, like the throat, breast, and under parts, piu^e white. 
The term ^masked,' therefore, is more appropriately applied 
to this than to those species which have the whole head of 
a darker colour than the rest, resembling a hood. With the 
exception here mentioned, the whole plumage of this bird 
is coloured so much like that of the Laughing Gull, that we 
need not describe it. Its length is usually about thirteen 
inches, with a more slender bill and shorter feet. Those 
w^ho have seen this rare visitor, with its brown mask, say 
that it can readily be distinguished from its congeners ; but 
fev»^ have had this opportunity. One, in summer plumage, 
from Shetland, is described by Yarrell, and that is all ; 
although Temminck wrote of it as common in the Orkneys, 
and occasionally appearing on the coast of England. Some 
even doubt whether it is a distinct species. 
Sabine's, and Bonaparte's Mews, again, are both species 
of which British naturalists know little or nothing from 
actual observation. The first was discovered by Captain 
Sabine on the west coast of Greenland, at a breeding sta- 
tion on some low rocky islands, where it associated with 
the Arctic Tern. The second is stated by Swainson and 
Eichardson to be common in all parts of the Fur countries, 
and has been met with by Audubon in various parts of the 
east coast of North America. Very pretty birds are they 
