THE BI'EDS OF Xew JERSEY. 187 



both webs : tail, dusky, with bars of lighter mottling and subterminal white 

 spots on all but the middle pair ; below, breast black mottled with bufif and 

 white ; half collar on throat, pure white ; entire abdomen, sides and crissum 

 barred black and white. 



Adult female. — Similar, but no white spots on the tail, and throat patch buff. 



No nest; eggs, two, laid on the bare ground, grayish-white, thickly mottled 

 all over with dull brown, 1.20 x .85. 



Common summer resident. Arrives April 30th (May 11th), de- 

 parts October 10th. 



The Nighthawk is most frequently seen just before dusk ilying 

 high overhead in an irregular jerking manner, now and then diving 

 toward the ground, his long, narrow wings conspicuous from the white 

 spots, which look from below like holes. As he flies he utters a 

 peculiar harsh cry, which can be heard at a great distance, and seems 

 to come from much closer at hand than it really does. During the 

 daytime the Nighthawks may be found on the ground, or on some log 

 or fence rail, their mottled plumage blending well with their sur- 

 roundings and rendering them inconspicuous. 



They are wholly insectivorous, and capture their food on the wing. 



Family MICROPODID^. 



The Swifts. 



These birds are similar to Swallows, but have longer, narrower 

 wings, and projecting spines at the end of the tail feathers. We have 

 but one species. 



423 Chaetura pelagica (Linnaeus). 

 Chimney Swift. 



PLATE 42. 



Adults. — Length, 4.75-5.50. Wing, 5-5.25. Above, sooty black; feathers 

 with a slight gloss on the central part ; wings, black, with a slight bluish sheen ; 

 under parts, sooty gray ; throat and upper breast, pale gray ; a jet black spot 

 in front of the eye. 



Young in first summer. — Similar. 



Nest a basket-like structure of dead twigs fastened together and to the inside 

 of the chimney in which it is located by a gluey substance secreted by the bird ; 

 eggs, four to six, pure white, .75 x .50. 



