54. Larus delawarensis. 18 in.

Adults in summer. - White with pearl gray mantle; ends of outer primaries black with white tips; eye yellow; feet and bill greenish-yellow, the latter crossed by a black band near the tip. In winter, the head and neck are streaked with grayish. Young birds are mottled brownish-gray above, and the tail has a band of blackish near the end.

The adults can be distinguished from the Kittiwakes, which most closely resemble them, by the yellowish feet and white tips to the black primaries.

Nest. - In hollows in the ground, usually in grass. The two or three eggs are gray or brownish gray, strongly marked with black (2.80 x1.75). They breed in large colonies, often in company with other gulls and terns.

Range. - Whole or North America, breeding from New Foundland, Dakota and British Columbia northwards, most abundantly in the interior; winters from Northern United States southward.