NORTH AMERICAN BIRDS. 
i. Bill with a black band near tip. 
Adult: Mantle pale pearl-gray (much as 
in L. argentatus); bill greenish yellow, 
crossed near end by a very distinct black 
band, the tip sometimes tinged with 
orange; iris pale yellow, eyelids vermil- 
ion-red; feet (in life) pale yellow, some- 
times finged with greenish. Young: 
Above brownish dusky, the feathers 
broadly bordered and otherwise varied 
with pale grayish buff or dull whitish; 
quills blackish, the shorter ones bluish 
gray basally and tipped with white; tail 
with basal half (or more) pale grayish, 
the subterminal third (or more) blackish, 
the tip narrowly white; lower parts 
white, spotted along sides with grayish 
brown; bill blackish, paler toward base. 
Length 18.00-20.00, wing 13.60-15.%5, cul- 
men 1.55-1.75, depth of bill at angle .50- 
.65, tarsus 1.90-2.45, middle toe (without 
claw) 1.30-1.60. Hggs2.39 X 1.71. Hab. 
Whole of North America, breeding far 
northward; south, in winter, to Cuba 
and Mexico.......... 54, L. delawarensis 
Orp. Ring-billed Gull. 
f?. Bill without black in adult. 
jf. Gray “wedge” on inner web of third 
quill never tipped with white, and 
not carried definitely farther than 
tip of sixth, usually not much beyond 
tip of seventh, quill. Adult: Mantle 
pearl-gray (about intermediate in 
shade between that of L. californicus 
and L. argentatus); rest of plumage, 
except quills, pure white. Young: 
Head and neck soiled whitish, striped 
with grayish brown; back, scapulars, 
and wing-coverts dull grayish brown, 
margined with grayish white; basal 
half of tail white, terminal half 
blackish or dusky, narrowly tipped 
with white; lower parts dull white, 
spotted and otherwise marked with 
dull brown. Downy young: “Cov- 
