122 MEMOIRS OF THE NUTTALL ORNITHOLOGICAL CLUB 



which is its Cree name." This cry is emitted by both sexes and I have heard it 

 given from i6 to 36 times a minute. The bird flutters its wings quickly as it emits 

 the cry. Although Nighthawks are most active in the morning from the crack of 

 dawn to sunrise, and in the evening, I have heard the cry at every hour of the day 

 and night. When feeding the young, the adults may be seen hawking at mid-day, 

 and may be heard at midnight at time of a full moon. If the night is dark they 

 are not often heard. The hawking flight for insects is generally high up in the air 

 and the birds may sometimes be seen sailing with wings held up at an angle. I 

 have also seen them soar in circles, like a hawk, with wings fully extended. 



The courtship performance of the male is a spectacular one and may be seen 

 from the day of arrival from the South until early in August. The bird sets its 

 wings held up at an angle, and plunges with great speed obliquely downward for 

 the distance of a hundred feet or more, ending its plunge with an abrupt upward 

 curve and glide for about half the distance of the descent. During the downward 

 plunge and part of the upward glide a loud whirring or booming noise is heard, 

 which is probably made by the passage of the air through the stitT wing feathers, 

 a sound resembling that produced by the vibration of tense cords in violent gusts 

 of wind. 



During migrations the birds sometimes alight but are very difticult to see. On 

 September 9, 191 7, one alighted in the driveway of my Ipswich house and allowed 

 a close approach. On May 30, 191 3, at four o'clock of a sunny afternoon I 

 noticed on a small boulder on the side of Sagamore Hill what I first took to be a 

 lichen-covered bump, but on examining it with binoculars saw that it was a Night- 

 hawk. The bird, facing the wind and the sun, was flat on the rock with wings 

 and tail slightly projecting. The white spots on the rump and under the chin, 

 which helped to give the lichen-like appearance, were plainly visible with the 

 naked eye at fifty yards. I approached cautiously by zig-zags, — never walking 

 directly toward the bird, — five paces at a time until I was within fifteen feet. The 

 bird was evidently watching me through nearly closed eyes. At fifteen feet the 

 bird could stand it no longer and sprang into the air, joining another bird that 

 was flying about. 



187 [423] Chaetura pelagica (Linn.). 



Chimney Swift. 



Common summer resident. April 28 to October 4; average date of arrival 

 for nine years, May 4. 



Eggs: June. 



The late date of October 4 is recorded at Amesbury by DamselU for 1898. 



1 Allen, G. M. Auk, vol. 30, p. 27, 1913. 



