EASTERN NIGHTHAWK 217 



weather, the male left the elm tree during the day and flew about 

 uttering the usual 'peent calls. He was never seen on the roof during 

 the middle of the day. 



The female was always faithful to her task regardless of a parch- 

 ing sun or torrential downpours of rain. At one time the ther- 

 mometer placed on the graveled roof reached 130° F., although it 

 was only 98° F. in the shade on the street level. At such times her 

 enormous mouth was wide open, and she panted incessantly. The 

 female's presence was needed to protect the eggs from the excessive 

 heat fully as much as it wjis to supply warmth during the cool 

 evenings when the temperature sometimes dropped as low as 45° F. 

 If the female should leave her eggs when the temperature rises as 

 high as 130° F. the embryos inside of the eggs would be killed in a 

 few minutes. 



It was common for the heat to melt the tar beneath the 

 gravel so that it oozed to the surface of the pebbles. Milton Goff 

 (1932) relates an interesting experience of a nighthawk that nested 

 on a school roof at Eockford, 111. One of the two eggs became 

 firmly embedded in some tar melted by the sun. The female was 

 unable to move the ^^^ after nine desperate attempts made during 

 the course of two hours. 



Young. — In 1922 the nighthawks arrived at Brunswick, Maine, 

 on May 15. On June 3 the first egg was laid and was marked No. 1. 

 It was not incubated the first day. On June 4 the second <&gg was 

 laid at 11:05 a. m. and marked No. 2. The laying of the second 

 <ig'g was observed. It was seen when it first appeared and watched 

 until it emerged from the cloaca two minutes later. The egg was 

 moist at first but quickly dried in the warm air, after which the 

 female turned around and tucked it under her breast. Incubation 

 began immediately after the second egg was laid. , 



On June 23, 1922, egg No. 1 was pipped at 8 : 30 a. m. and at this 

 time the peeps of the confined embryo could be heard distinctly. At 

 11 : 00 a. m. the chick had emerged. The ^gg shells of the first egg 

 were removed about noon. The female took them in her beak and 

 dropped them during flight at a point about a hundred yards from 

 the building. Egg No. 2 was pipped at 2 p. m., and at 3 p. m. 

 portions of the shell were broken away. The female seemed little 

 concerned about the first chick but lavished all her attentions on the 

 unhatched bird. At times she elevated her body, peered at the ^gg-, 

 and responded to the calls of the embryo with an assuring note. She 

 frequently rocked her body over the egg as if to assist in removing 

 the shell. At 6 p. m. the shell was cracked latitudinally and soon 

 thereafter the cup of the larger end was slightly lifted. At 6 : 30 

 p. m. the young was completely freed from the shell, which broke 



