392 Field Museum of Natural History — Zoology, Vol. IX. 



Female: Length, 9.10 to 10.05; wing, 5.20 to 5.40; tarsus, 1.25 

 to 1.40; bill, 1.25 to 1.40. 



Male: Length, 8.40 to 9.10; wing, 4.60 to 4.90; tarsus, 1.20 to 

 1.30; bill, 1.20 to 1.30. 



Wilson's Phalarope is a rather common summer resident and breeds 

 in northern Illinois and Wisconsin. The male of this species, as in 

 the other Phalaropes, is smaller than the female and not so highly 

 colored; he also takes upon himself many domestic duties usually 

 assumed by the female; he sits on the nest, contrary to the usual 

 custom, and devotes himself to the young chicks. The nest is merely 

 a slight depression in the ground, more or less lined with grass. The 

 eggs are usually four, cream white, heavily blotched with dark brown, 

 and measure about 1.25 x .95 inches. 



Family RECURVIROSTRID.E. Avocets 



and Stilts. 



A small family characterized by long slender legs and extreme 

 slenderness of bill. Two species occur in eastern United States. 

 They are usually seen in flocks wading about in shallow water, but 

 they are expert swimmers as well as waders. 



Genus RECURVIROSTRA Linn. 



105. Recurvirostra americana Gmel. 

 American Avocet. 



Distr.: Temperate North America, north of the Saskatchewan 

 and Great Slave Lake, south to Guatemala and the West Indies in 

 winter; rare in eastern United States. 



Adult in summer: Bill, very slender and curved upwards; feet, 

 partly webbed; general plumage, white, becoming cinnamon brown 

 on the head and neck, but remaining whitish at the base of the bill; 

 primaries, black; most of the secondaries, white, forming a broad 

 white patch on the wing; tail, ashy gray; legs, bluish; bill, black. 



Adult in winter: Head and most of the neck, ashy gray; tail, 

 ashy gray; rest as in summer plumage. 



Length, 18 to 20; wing, 7.50 to 9; tail, 3.50; bill, 3.25 to 3.75; 

 tarsus, 3.60. 



