28 



and various lepidopterous larvae. The third of the young was 

 hatched early on the following day (May 15). 



Occasional notes were taken until May 19, w'hen all-day ob- 

 servations were made and continued on May 20 and 21, thus 

 giving complete data for the sixth, seventh and eighth days in 

 the life of the tw^o older nestlings. Frequent observations — in- 

 cluding the weight of the young — w'ere made ]\Iay 22-25, and 

 on ]\Iay 26 all-day observations were resumed and continued 

 until the young left the nest on the morning of May 28, the 

 fifteenth day. 



Quantitatively the data -on the feedings for these five com- 

 plete days are fairly accurate; qualitatively they are not as sa^- 

 isfactory as could be desired, although several pieces of food 

 were obtained and identified through the courtesy of the state 

 entomologist's office. 



For the five days of full observation, the working day — 

 meaning the period of activity of the parents at the nest — 

 averaged nearly 15^ hours, from 4 a. m. to 7:30 p. m. At 

 first the female brooded throughout the night, but toward the 

 end of the period, when the fairly fledged young filled the 

 nest, both parents w'ere absent at night. On the sixth day 

 (]\lay 19) the number of broodings — number of times the 

 female settled — was 17; the minimum duration of a single 

 brooding was 5 minutes, the maximum 65 minutes, the average 

 28 minutes. Thus the young were brooded on their sixth day 

 for a total of 8 hours, or somewhat more than half of the 

 working day, or daylight period. Two thirds of the feeding was 

 done by the male. In contrast with this, on the thirteenth 

 day (May 26) the female did not settle once during 

 the day, nor did she spend the previous night or the following 

 night upon the nest. During the day, while near the nest, 

 she perched either on the edge of the nest or near by on the 

 window-sill. Once she stood over the nest. Usually, how- 

 ever, she left promptly after feeding. The cock robin did less 

 than one third of the feeding on this day. 



For the five days on whicli complete data were taken, the 

 number of feedings was as follows: 



