60 The Wilson Bulletin— No. 83. 



which left the nest in the morning'. It is not known whether 

 the female brooded the entire night or whether the male re- 

 lieved her, althoug-h there is no reason to suspect that such 

 a change took place. The attitude of the female in sleep was 

 to turn her head to the left, backwards and tuck the bill un- 

 der the wing. 



Sanitation. 



The parent birds were very careful as to the cleanliness of 

 the nest. The mother bird seemed to be more particular in 

 this matter, for she did more than an equal share of work in 

 keeping the nest clean. 



From the beginning of the observation up to the snake in- 

 cident the parent birds failed to catch the excreta sac only 

 fifteen times. While, from this time on to the departure of 

 the young she failed thirty-four times. But it must be borne 

 in mind, that during this latter period the responsibility of 

 caring for the young rested entirely upon the female. With 

 this extra share of labor it was not surprising that she occa- 

 sionally missed the excreta sac. This circumstance was, of 

 course, an abnormal one. The records show that in many of 

 these instances the excreta sac was voided " immediately fol- 

 lowing the departure of the female, after feeding one of the 

 young." Several times when the sac fell to the ground the 

 female picked it up and carried it away. Again the female 

 made more feeding visits, per young, for, as the nestlings 

 grew, they demanded more food. And, too, as the birds 

 became older and larger their bodies often projected over 

 the rim of the nest. Table IV shows the number of times 

 each day that the excreta sac was not caught by the parent. 



TABLE IV. 



Showing the total number of times each day the excreta sac 

 was not caught when voided. 



July 2 3 4 5 6 7 8 9 10 11 12 Total 



Not caught 4 1 6 2 3 5 10 15 3 49 



Total number of 



excreta sacs 13 38 41 34 34 49 45 35 39 32 3 363 



