848 



U. S. p. R. R. EXP. AND SURVEYS — ZOOLOGY — GENERAL REPORT. 



LAEUS SUCKLEYI, Lawrence. 



Suckley's Gull. 



Larus suckleyi, La«r. Ann. Lye. N. H. N. Y. VI, 1858,264. 



Sp. Ch. — Mult. Head, neck, under plumage and tail, pure white ; back and wings clear pearl blue ; ends of the primaries 

 black, occupying about half the length of the first and decreasing to the seventh, on which it consists only of a sub-terminal 

 spot ; the first primary has a white spot over both webs an inch and a half in extent inside the tip, the second has a similar 

 mark of white, but less in extent ; the tips of the first and second primaries are black, but of all the others white ; the 

 secondaries and tertiaries largely marked with white at their ends ; bill dusky yellowish green, except on the ridge of the upper 

 mandible, forward of the nostrils, and on the angle of the lower mandible, which parts are orange yellow ; tips of both 

 mandibles pale yellow ; legs and feet greenish yellow. 



Length, 17| inches ; alar extent, 43^ ; wing, 13^ ; tail, hi ; bill, 1 5-16; tarsi, 1|. 



young-. Mottled with grayish white and dark ash ; wings and tail dark brown, the latter ashy white at the base and tip ; bill 

 flesh coloi for half its lengtli from the base, terminating with black ; legs and feet flesh color. 



Hab. — Pacific coast ; Puget's Sound. 



Four specimens are in the collection. 



List of specimens. 



BLASIPUS, Bonaparte. 



Blasipus, Bon. 1852. 

 Ch . — Bill long and rather slender ; general color dusky ; of medium size. 



Bonaparte enumerates three species under this genus, only one of which inhabits our coast ; 

 in my opinion he has improperly placed "belcheri" and "fuliginosus" (closely allied species, 

 if not identical with the above,) in a different genus, viz : Leucophaeus, the type of wliich is 

 " haeinatorhynchus," a species having the bill very robust. 



BLASIPUS HEERMANNI, Bon. 



The White-headed Gull. 



LorusAccrmonm, Cass. Proc. Acad. N. Sec. Phil. VI, 1852, 187.— Ib. Ills. I, 1853, 28; pi. v. 

 Melarus heermanni, Brucii, Cab. Jour. 1855, 279. 

 Blasipus heermanni, Bon. Cons. Av. II, 1856, 211. 

 Sp. Ch. — Jidull. " Bill red, both mandibles tipped with black ; feet and legs dark ; head white, which color gradually blends 

 into an ashy lead color, enveloping the entire body above and below, darker on the back and wings and paler ou the abdomen. 

 Secondary quills tipped with white, forming an oblique bar when the wings are folded. Superior coverts of the tail very pale 

 cinereous, nearly while. Quills and tail feathers brownish black, all of the latter narrowly tipped with white. Shafts of the 

 two first primaries white on the inferior surface of the wing." 



"Total length, about 17j inches; wing, 13! ; tail, Sj ; bill from angle to tip of upper man<lible, 2; inches." 

 " Young. Smaller; total length, about IG inches ; wing, 13 ; tail, 5 inches. Entire plumage brown, darker on the head and 

 paler on the under surface of the body ; quills and tail feathers bruwiii^li black, the latter narrowly tipped with white." 

 Hah. — Coast of California. 



