THE NATURAL HISTORY SURVEY. II3 



A very common resident, though a large number are some- 

 what migratory, arriving early in April and departing in October, 



Its range covers eastern and northern North America, south 

 to North CaroUna, west to the base of the Rocky Mountains. Oc- 

 casional on the Pacific slope, from California northward. 



ORDER MACROCHIRES: GOATSUCKERS, 

 SWIFTS. 



FAMILY CAPRIMULGID.ZB: GOATSUCKERS, ETC. 

 Genus ANTROSTOMUS Goujd, 1838. 



Antrostomus vociferus (Wilson). Whip-poor-'will. 



Caprimulgus vociferus Wilson, Amer. Orn., V, 1812, 71, pi. 41, figs. 



1-3. 

 Antrostomus vociferus Bonapaete, Geog. & Comp. List, 1838, 8. 



Formerly this species was a common summer resident, but now 

 it is quite rare. It arrives the last of April and departs in 

 September. Mr. Robert Kennicott includes this species in his 

 list* of Cook County birds with the annotation "Abundant. 

 Found throughout the state.'' He also states that it nests in 

 Cook County. In 1876, Mr. E. W. Nelson reportedf that it was 

 a "comm®n summer resident." 



Its range includes that portion of North America east of the 

 Great Plains, and from about latitude 50° in the interior south 

 through eastern Mexico to Guatemala. 



Genus CHOBDEILES Swainson, 1831. 



Chordeiles virginianus (Gmelin). Nighthawk. 



Caprimulgus virginianus Gmelin, S. N., I, ii, 1788, 1028. 



Chordeiles virginianus Swainson, in Sw. & Rich., Fauna Bor. Amer., 



II, 1831, 496. 

 Chordeiles popetue Baird, B. N. Amer., 1858, 151. 

 Popular synonyms : Bull Bat. Whip-poob-will. 



The Nighthawk is a summer resident but it is more common 

 during its migrations, especially that of the fall. Mr. E. W. 

 Nelson makes the following statement :f "A common summer 

 resident. Arrives the loth of May and departs in immense 

 flights, often lasting several hours, the first of September." Mr. 

 Nelson also records the finding of variety henryi at Waukegan, 

 a few miles north of our limits, by Mr. Rice in July, 1875. He 

 says that this specimen was the first one taken in this vicinity, 



*Trans. Illinois State Agri. Society, Vol. I, 1853-1854, 581. 



tBirds of Northeastern Illinois. Bull, of the Essex Institute, Vol. VIII, 1876, 114. 



