Gulls. 
LZ (lite ZEEE. 
Us 
39. Ivory Gull (Pagophila alba). L.17. Ads. Pure 
white; bill yellow; feet black. Yxg. Similar, but wings 
and tail tipped with blackish; throat dusky. 
Range.—Breeds in Arctic regions; winters south to Great Lakes 
and British Columbia; rarely to Massachusetts. 
40. Kittiwake (Rissa tridactyla). L. 16. Hind toe 
naila knob. Ads. Head, neck all around, underparts, 
and tail white; 3 in. or less, of tips of primaries black. 
Yung. Tip of tail, ear-coverts, nape, and wing-coverts 
with black; bill black; inner web of primaries with 
white. Notes. A rapidly uttered hit-a-wake, it-a- 
wake. 
Range.—North Atlantic and eastern Arctic regions; breeds in Amer- 
ica, from Gulf of St. Lawrence to Greenland; winters south to Great 
Lakes, Long Island and, rarely, Virginia. 
40a. Pacific Kittiwake (Rissa trddactyla pollicaris). 
Similar to No. 40, but hind toe more developed; black 
tips to 3 outer primaries, 3 in. or riore in length. Notes. 
‘*A shrill, harsh cry when disturbed and a low whistle 
when communicating with each other.’’ (Nelson.) 
Range.—‘‘North Pacific and Bering Sea; south in winter, casually 
to southern California.’’ {A. O. U.) 
41. Red-legged Kittiwake (Rissa orevirostris). Ads. 
Similar to Ad. of No. 40, but legs red, back and inner 
web of primaries darker; bill shorter, 1.2. Yug. Sim- 
ilar to No. 40, but no black on tail or wings. 
Range.—Coasts and Islands of Bering Sea.’’ (A. O. U.) 
54. Ring-billed Gull (Larus delawarensis). L. 18. 
Ads., summer. bill greenish yellow, a black band across 
tip; ends of primaries black, a white spot near tip of 
outer one. Ads. Winter. Similar, but head and neck 
streaked with grayish. Yug. Tail grayish with a 
broad black band; primaries black; back brownish gray 
and whitish; belly white; end half of bill black. 
Range.—North America, coast and Interior; breeds from Newfound- 
land, southern Minnesota, and British Columbia northward; winters 
from Nova Scotia and British Columbia south to Cuba and Lower 
California. 
55. Short-billed Gull (Larus brachyrhynchus). L. 17; 
B. 1.50 Ads., summer. Head, neck, tail, and underparts 
white. Two outer primaries tipped with black, their 
white spaces followed by black; remaining primaries 
tipped with white. Yxg. Grayish brown; basal half 
of tailpearl. Notes. ‘“‘A sharp querulous Awew-kwew,’’ 
(Nelson.) ’ 
Range.—North Pacific; breeds in Alaska and interior of northern 
British Columbia; winters on coast from British Columbia to southern 
California. 
