EISSA KOTZEBUI. 
PACIFIC KITTIVAKE. 
EISSA NIYEA. Bruch. Mon. Larid. Cab. Jo urn (1853), p. 103, sp. 31. 
EISSA BBEYIEOSTEIS. Lawr. B. of N. Am., p. 855. 
EISSA KOTZEBUI. Boot. Consp. Gen. Av. (1857), p. 226. Coues. Eev. of the Gulls of N. Ain., Proc. Acad. Nat. Scien. (1862), p. 305. 
This bird comes from the north-west coast of America, and bears a very close resemblance to the Kittiivake ( Rissa Tridactylus) of our 
own shores. The chief differences are, that the Pacific Kittiwake has a somewhat longer bill, and a more developed hind toe; rather 
unsatisfactory variations, it must be confessed, to establish a species of Gull upon. The specimen from which the figure in the plate 
was drawn is a young bird, but the only one obtainable, for although it is common enough in its accustomed places of resort, but few 
examples have yet been procured for the cabinet. I am not aware that a fully adult bird is in any American collection, Dr. Coues 
not even having had one when he was investigating this family ; and until such are received, the exact relationship existing between 
this bird and the common Kittiwake cannot, with any degree of certainty, be established. The mere fact of a widely different habitat, 
would not, of itself, suffice for considering them distinct. 
Nothing is known of its economy or habits. 
The specimen may be described as follows : 
Head and neck white, excepting a post ocular spot and nape, which are dark gray. Mantle grayish blue. Primaries blackish brown, 
with black shafts, the inner webs white at the base, this hue narrowing as it proceeds towards the tips. The white increases in extent 
and width on the different feathers, unto the fifth primary, which is bluish white, with a brownish black tip, and a dusky hue running 
along the shaft. Eemainder of primaries similar to the back, but lighter, becoming white on their edges. Secondaries white, for almost 
their entire length. Eest of plumage pure white ; an indistinct, imperfect, subterminal dusky bar on the tail. 
Bill yellowish, tinged with olive ; tip dusky. Tarsi and feet olivaceous. 
The figure is life-size. 
YELLOW-BILLED GULL. 
LAEUS NIYEUS. Pall. Zoog. Eoss. Asiat. Yol. II. (1810), p. 320, PI. XXIY, 
LAEUS BEACHYEHYNCHUS. Gould. Proc. Zool. Soc. (1843). 
EISSA NIYEA. Lawr. Eep. P. E. E., p. 855. 
EISSA BEACHYEHYNCHUS. Coues. Eev. Larid., Proc. Acad. Nat. Scien. (1862), p. 306. 
This rare species is a native of Kamschatka, but probably, in some of its wanderings, it visits our own shores. A single specimen 
is in the collection of the Academy of Sciences of Philadelphia, and is represented in my plate. Nothing has been recorded of its 
habits, the distant regions where it finds its home being too difficult of access to enable many ornithologists to become acquainted 
with it in its haunts. 
There seems to be a certain amount of doubt among naturalists as to what is the proper name for this bird ; whether it is 
the Larus Niveus of Pallas, or the Eissa Brachyrhynchus of Gould. Pallas gives an imperfect, unsatisfactory description, and refers to 
a previous species (L. Cachinnans), when speaking of the primaries, which, if they should be identical in their markings, would, of 
necessity, make Pallas’ bird a very different species from the one here represented. But the figure which he gives in the plate above 
referred to, and which is certainly a very good one, presents to us a bird almost, if not entirely, identical with the one exhibited 
in my plate. I say almost, as there are a few slight discrepancies, which have been deemed by some authors as sufficient to throw' 
Pallas’ species on one side, so far as regards its claim to be considered the same as the present bird. The text says the bill is virescente- 
flavum. The plate exhibits it as yellow. In the description, the feet are said to be fusel ; in the plate they are brownish. The 
text refers the primaries to L. Cachinnans, which are black, with apical white spots. The plate represents these as they are in the 
