NESTS AND NEST-BUILDING IN BIRDS 355 



in places where the paper or yellow birch is unknown this ad- 

 mirable material often forms the sole garnish or fixative for 

 the outer surface. Again even where such substances abound 

 they may be entirely neglected, and the outer surface of the cup 

 left very loose and rough. 



There was usually a long pause at about noon when for an 

 hour or more nothing was accomplished, but at other working 

 times their visits would occur every two or three minutes. 

 Towards the close of this day and even earlier, many long strips 

 of bark were hanging free from the entire outer surface of the nest, 

 a condition most noticeable in the oriole (compare fig. 21), 

 and a very characteristic act at this period was either to stand 

 on the twig and bend low, or to cling to it with head hanging 

 down, and quickly picking up one strand at a time, work them 

 with bill into the nest-wall. 



The third day at this nest opened with threatening weather, 

 and according to Mrs. Ruedy, who watched the building, work 

 was not. resumed with any regularity until about 9 a. m., when 

 bark and silk were still being laid. When we were able to visit 

 this nest again at 3 p. m. the female was quietly sitting in what 

 was now a very serviceable structure, occasionally picking 

 at its rim and outer surface, and adjusting or firming it a bit 

 here and there. In reality the work of construction lasted 

 nearly five days , but from the close of the third day until the 

 end of the fifth the more active labor gradually slowed down, 

 when the female would sit in her egg-cup for longer and longer 

 intervals, until on the sixth day from the start she remained 

 to lay her first egg, after 7.30 o'clock in the morning. 



At such times of entering the nest referred to above, and be- 

 fore the appearance of eggs, the bird would sit deep, and 

 repeatedly mold, turn and mold again, scratching with feet, 

 and shaking all over with the violence of her effort; then she 

 would often rise, and dropping her head inspect the inside of 

 the cup, or spend much time in fussing with threads and fixing 

 strips of bark; then more molding movements would follow 

 with perhaps inflation of the throat, and erection of feathers 

 of head and neck, and a cocking of the head from side to side 

 as she peered eagerly about. 



The second egg was deposited on the morning of the following 

 day, and also before 7.30 a. m. On the morning of this day 



