128 AMERICAN ORNITHOLOGY. 



NIGHTHAWK, 



A. O. U. No. 430, (Chordeiles virginianus.) 



RANGE. 



In summer the common Nighthawk may be found in North America, 

 east of the Plains and south of the middle portions of Canada. The 

 Western Nighthawk, (Chordeiles virginianus henryi), is found west of 

 the Mississippi River and south from British Columbia. In winter both 

 varieties leave the United States. 



DESCRIPTION. 



Length, about 9.5 in,; extent, 24 in.; tail 4.5 in. Eye, brown. Bill 

 and feet very small in comparison to the size of the bird, the former 

 being scarcely a quarter of an inch in length, although the gape is fully 

 an inch and a half, thus forming an extremely large mouth in connec- 

 tion with a very small bill. Mottled above with black, gray and tawny. 

 Below, barred with black and dull white. A large white bar across the 

 throat; also one across the primaries formed by a single large white 

 spot about midway on each of the five outer primaries. A white band 

 across the tail near the end. The female differs from the male in 

 appearance in that the white of the throat and tail is replaced by tawny 

 and on the latter may sometimes be lacking. The western form differs 

 from the eastern very slightly if at all. The general average is sup- 

 posed to be a trifle lighter in color than the eastern. The young birds 

 have all the characteristic markings of the old but the under parts are 

 more closely and distinctly barred. 



NEST AND EGGS. 



l9 



The nighthawks make no attempt at nest building. Their two eggs 

 are laid upon the bare rocks or upon the rock lichens and moss that are 

 common in localities where large boulders just peeping up above the 

 surface of the ground are common. The eggs are mottled with vary- 

 ing shades of white, gray and black, and are laid late in May or during 

 June. About large cities it is not an uncommon occurrence for these 

 birds to nest ur)on the gravel roofs of large buildings. The eggs re- 

 semble very closeiy the rocks upon which they are laid and are difficult 

 to distinguish. The eggs of the western bird average a trifle lighter 

 than the eastern. 



