190 NATURE-STUDY REVIEW [11:4— Apr., 1915 



As shown by the above table, on July 13, when the young were 

 14 days old, the birds were watched for four hours at different 

 times of the day, showing an average of 19^ feedings per hour. 

 For the day of 15}/^ hours this would mean 303 times per day. 

 Taking the average between this and 238, the times the young 

 were fed when 2 days old, we get 270 times as the average number 

 of times the young were fed daily during the period they were in 

 the nest. Multiplying this by 15 the number of days in the nest, 

 we get 4050 as the total number of times the young were fed. As 

 the parents often brought more than one insect at a visit, the rear- 

 ing of this \vren family meant the destruction of from four to five 

 thousand insects. 



The largest number of times the young were fed in an hour was 

 25, immediately after a storm when the young were 12 days old. 

 The smallest number of times was eight during a heavy shower 

 when the birds were two days old. 



Some differences were observed between the male and female in 

 their activities and habits. During the first days of rearing the 

 young, most of the feeding was done by the female alone, but later 

 more assistance was given by the male, until on the last day the 

 work was about equally divided between them. 



During one day the male always left and entered the tree to 

 which the nesting house was fastened by the east side, while the 

 female came from the west side. On another day they both came 

 from the west side. 



On all occasions the female approached the house directly, flying 

 at once to the entrance, frequently disappearing inside before one 

 could focus the field glasses on the house. On the other hand, the 

 male approached gradually, hopping from twig to twig, and singing 

 sometimes waiting five minutes, and on one occasion 1 1 minutes, 

 before feeding the young. Sometimes he waited till the female 

 returned and then fed immediately after she left. 

 ' Sometimes the female remained in the house for periods varying 

 from one minute to six minutes. The male always came out 

 immediately after feeding. 



The following data, furnished by Edward Uehling for two pairs 

 of wrens which he observed, shows the total time occupied by the 

 wren from the time of beginning to build the nest till the young 

 leave it. 



