220 BULLETIN 17 6, UNITED STATES NATIONAL MUSEUM 



youngster, whereupon it ignored its parent to enjoy the comfort pro- 

 vided by the cool sponge. This act probably aided the survival of 

 the young nighthawk through the remainder of the record-breaking 

 hot day. 



As the nighthawk grew older he became very aggressive and 

 pugnacious and never hesitated to pester his mother whenever he 

 was hungry. At times he seemed mischievous. It was not a rare 

 experience to see him crouch under his mother's breast and then by 

 standing up quickly and rigidly topple his mother so that she was 

 forced to extend her wings to keep from falling over. During the 

 period of the rapid growth of the wing feathers the youngster was 

 continually extending and stretching his wings as if to relieve the 

 uncomfortable feeling caused by growing pains. 



Wlien the young nighthawk was three weeks old he was able to 

 make short flights from one place to another on the gravel roof. At 

 this stage of his growth he had become so large that it was difficult 

 for the female to cover him adequately while brooding. This was 

 strikingly demonstrated on the evening of July 17, when he was 23 

 days old. The mother had left him alone on the roof while she was 

 away on her regular evening search for food. It was so cool and 

 damp that the young bird uttered notes that clearly indicated dis- 

 comfort. I placed him in a woolen bag, and this, combined with the 

 warmth of my hands, was very satisfying, as indicated by his change 

 to notes of contentment. He remained there in comfort until his 

 mother alighted on the roof and gave the characteristic call note, 

 announcing supper. The little nighthawk struggled out of my bag 

 and ran directly to his mother to be fed. After he was gorged with 

 insects, the female attempted to brood him, but to her apparent dis- 

 may he rushed back to the woolen bag, clearly recognizing that I 

 could do a much better job at brooding. 



On July 19, when the nighthawk was 25 days old, I discovered 

 that he was no longer solely dependent on liis parent for food. I 

 found him busily engaged catching some white moths that had 

 collected about a drain pipe of the roof. He was flying this way 

 and that, catching the moths with great delight. As I sat there 

 watching I chanced to pull a small handkerchief from my pocket, 

 whereupon he dashed at the white object with the ferociousness of 

 a tiger. Evidently to the nighthawk this was some giant moth large 

 enough to provide for an entire meal. 



The female now made frequent attempts to entice the young bird 

 away from the roof by first offering food but flying away before it 

 was delivered. The youngster would follow her in extended flights 

 but invariably returned to the roof. 



On July 24, when the bird was 30 days old, the female was photo- 

 graphed with the young for the last time. Thereafter she forsook 



