NEST STUDY OF MARYLAND YELLOW-THROAT 7 
TABLE III 
CLASSIFICATION OF NESTLING Foop 
1. Unidentified Insects 376 
2. Moths 347 
S7e WWorms 2” 290 
4, Spiders 280 
5. Mayflies 116 
6. Flies 61 
7. Unrecognized material 92 
8. Caterpillars 20 
9. Damselflies 54 
10. Beetles 13 
11. Chrysalids 13 
12. Butterflies 11 
13. Seeds 10 
14. Caddisflies 3 
15. Grasshoppers 6 
Total 1694* 
BROODING 
Brooding at the nest was performed entirely by the female. 
During the first few days after the hatching of the young she 
was on the nest most of the time. She would, however, make 
short trips from the nest and bring food to the young; she may 
also, on these occasions, have secured food for herself. Later, 
she did not brood regularly during the day at all, but always 
did at night. However, on the last night she was not on the nest 
at 8:25 Pp. mM. when the young had settled for the night, and 
she was not there at 4:30 o’clock the next morning. It may be 
then that night brooding is ecntrolled by a separate instinct 
whose intensity diminishes directly with the growth of the 
birds. 
In the early days of the brooding she would step on the birds, 
sit down, and fluff out the feathers. But during the latter part 
of the period she would stand on the sides of the nest and lean 
over. The sitting posture seemed to get more uncomfortable 
as the birds became older and more active. 
*This is larger than in Table II because at times the observer recognized 
several insects in one feeding. This fact is not noted in Table I or II. 
