JAN., 1909. BIRDS OF ILLINOIS AND WISCONSIN CORY. 619 



Young birds resemble the adult female. In changing to adult 

 plumage the male shows irregular patches of steel-blue. 



Length, 7.50; wing, 5.75; tail, 3.60; bill, .40. 



The Purple Martin is a common summer resident throughout 

 Illinois and Wisconsin, arriving from the south in April. 



Breeds in May and June. The nest is in holes in trees or about 

 houses or in boxes. The eggs are pure white, usually from 4 to 5 

 in number, and measure about .98 x .72 inches. 



Genus PETROCHELIDON Cabanis. 



283. Petrochelidon lunifrons (SAY). 



CLIFF SWALLOW. 



Distr.: Whole of North America, north to Ungava and Alaska, 

 breeding throughout its North American range; south in winter to 

 Mexico, Central and South America. 



Adult: Forehead white or brownish white; crown, back and a 

 small patch on middle of lower throat and upper breast, dark steel- 

 blue; chin, throat, and sides of the head, 

 rufous chestnut; shorter upper tail cov- 

 erts, dull rufous brown; breast and 

 sides, grayish, tinged with rusty brown, 

 whitening on the belly; under tail coverts, 

 long, extending to within half an inch or 

 less of end of tail feathers. 



Sexes similar. 

 Length, 5.25; wing, 4.40; tail, 2.50; bill, .30. 

 An abundant migrant and a common summer resident, arriving 

 from the south in April or early in May and leaving again in Sep- 

 tember. 



The nest is gourd-shaped, composed of mud and dry grass and 

 attached underneath overhanging cliffs or the eaves of buildings. 

 The eggs are 4 or 5 in number, pure white, and measure about .81 

 x .54 inches. 



