procured. I am not aware that any of the late Arctic voyagers obtained others ; nor has greater success
attended the Greenland correspondents of the Danish naturalists.”

“The occurrence of the same species of Gull on the internal waters of both the Old and New Worlds,”
remarks Mr. Newton, “is unique ; and it is still very desirable that examples from Siberia should be care-
fully compared with others from North America, so that we could feel assured of their specific identity.”

On the continent of Europe, one has been killed on the coast of Holland, a second on the Rhine, and a
third near Rouen ; and Temminck notices that there is one in the museum at Vienna. In temperate America,
Audubon states that he saw one flying over the harbour of Halifax in Nova Scotia, and that on one occasion
great numbers were seen about one hundred miles off Newfoundland.

The immature plumage of this Gull, and the forked form of its tail, remind us of the Terns ; in the latter
character it differs conspicuously from the square-tailed Chroicocephalus ridibundus ; but sufficient is not yet
known of its habits and actions to enable one to say if there be anything peculiar in its flight, if it be more
swift on the wing or more buoyant in the air than those Gulls which have the tail square ; in all probability
it differs in these as in other respects.

«Although the Larus Sabini,” says Mr. Thompson, ‘approximates to the Larus minutus in general
appearance, the plumage of the first year as well as that of maturity being very similar in both species, the
superior size of the Z. Sabinz, its tail being forked to the depth of an inch, and the comparatively greater
length of its tibia and tarsus may always (even in a preserved state) be sufficient specific distinction. In
the form of the tail, the Z. Sadéni approaches the typical species of Sterna more nearly than its congener
the Z. minutus. The latter, however, resembles that genus more in the form of the bill and in the dimen-
sions of the tarsus and tibia.”

In the adult, the entire head and throat are deep slate-grey, bounded posteriorly by a narrow band of deep
black; back of the neck, all the under surface of the body, the underside of the wings, the greater wing-
coverts, the secondaries, the upper tail-coverts, and the tail are white ; back, scapularies, and lesser wing-
coverts grey, primaries black, broadly margined for nearly the whole of their length and tipped with white ;
base of the bill black, the tip of both mandibles yellow ; inside of the mouth and edges of the eyelids ver-
milion-red ; legs and feet black.

The following is Mr. Thompson’s description of the autumnal plumage of the young bird in its first year :
— The forehead, space immediately above the eye, and between it and the bill (with the exception of the
narrow line of greyish black closely encircling the front and lower part of the eye), upper part of the throat,
and sides of the neck are white; crown, nape, and back of the neck blackish grey ; back, scapularies, greater
and lesser wing-coverts blackish grey tinged with yellowish brown, the extremity of every feather varying
from greyish white to white as it approaches the tail ; under part of the throat and upper part of the breast
pale ash-colour ; lower breast and all the under plumage white ; shafts of the first six primaries brownish
black at the base, becoming gradually darker towards the extremity, where they are black in the first three,
but in the fourth, fifth, and sixth assimilate in colour to the feathers at that part, which is white; the entire
of the outer webs of the first five are black ; the inner webs with a broad edging of white to within one to
two inches of the end, which part is black in the first three, but tipped with white in the fourth and fifth ;
in the sixth the inner web is white, the outer black, except for three or four lines from the tip (where it is
white), and again at about an inch from the end (where a white spot of an oval form appears); feathers of
the tail white, with black tips.”

The Plate represents an adult and a young bird, of the size of life. The figure of the latter was taken
from an English-killed specimen kindly lent to me for the purpose by E. H. Rodd, Esq.