Nest-Building 155 



not, they fly to a high or advantageous perch, and listen at- 

 tentively before making another move. 



On leaving the nest the female was rarely joined by her 

 mate, who escorted her to the spot where materials were sought, 

 but his efforts stopped at this point. In bringing a ball of mud 

 in the course of the morning, the hen came to the branch in the 

 habitual way, walked straight into the nest, and spent ten 

 minutes, the longest recorded time, in the work of molding. 

 She sat deep down, her head and tail only being visible under 

 the rim, shaking and turning most of the time. Suddenly, 

 with a low cut-cut ! she was off and in less than a minute returned 

 with another lump. 



In the course of the afternoon of the second day, dry grass 

 was added as a lining to the nearly completed nest, when the 

 same turning movements were repeated; but now the custom 

 of sitting quietly for a few seconds at a time, as if laying or 

 incubating an egg, became more frequent, after which would 

 follow more pulling at the materials, and shaking until every- 

 thing was all a-quiver again. The mud which was brought 

 after this time was apparently incorporated into the nest's rim. 



Operations were resumed early in the morning of the third 

 day, and continued about four and a half hours. At half-past 

 8 o'clock I found this Robin sitting quietly in her nest. After 

 adding a few more touches, and uttering a subdued note as if 

 expressive of her satisfaction in the work, she flew away. When 

 an hour had passed, and she had not returned, I decided to 

 inspect the new abode. It was evidently finished; the walls 

 were firm and true, the rim perfect, and the whole was lined with 

 dry brown grass of a rather fine quality, according to the ancient 

 rules of this guild. 



Three eggs were laid June 28-30, between 10.30 and 11.30 

 A.M. Incubation began June 29, after the appearance of the 

 second egg, and lasted thirteen days; two young were hatched 

 and one egg was addled. At each recorded visit material was 

 brought and incorporated into the nest. The rate of building 

 and the total number of loads of materials which went into this 

 nest are estimated from exact records extending over nine hours. 



