32 NORTH AMERICAN BIRDS. 



h 1 . 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 tinged 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 subtefminal 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 13.60-15.75, 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. Eggs 2.39 X 1-71. Sab. 

 Whole of North America, breeding far 

 northward ; south, in winter, to Cuba 



and Mexico 54. L. delawarensis 



Ord. Ring-billed Gull. 

 A 2 . Bill without black in adult. 



f. 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. calif ornicus 

 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- 



