SOUTHERN AMERICAN REDSTART 663 



and then to the left, making usually a half but sometimes a whole turn and, 

 with her head and breast, pressing the materials Avhich she had brought into 

 the meshes of the framework until they were completely filled. Working thus, 

 always from the inside, she modeled and remodeled until by the constant appli- 

 cation of fresh material she had transformed the original skeleton framework 

 into a compact, firmly-woven nest. Occasionally she would drop directly into 

 the nest without first alighting outside but she did not attempt to perch on its 

 rim until it was nearly completed. 



After putting in the lining, which consisted of horse hair, dry grass, and 

 shreds of birch, grapevine and mullein bark, she drew the loose ends which 

 had been left projecting or hanging down around the outside of the nest. These 

 ends were drawn and tucked in to bind the lining and were held down by the 

 bird's breast until all within her reach were secured. She then managed to 

 rub them still more firmly into place by cx-aning her head over the rim of the 

 nest and bringing her bill, throat and neck to bear on its top and inner and 

 outer surfaces at one and the same time. 



After this nest was finished, it was frequently visited by Black and White 

 Creepers, Yellow Warblers and Red-eyed Vireos, all of whom attempted to 

 appropriate some of its component materials for their own domiciles. They 

 sometimes succeeded in getting away with a few strands despite the vigilance 

 of the Redstart, who defended her castle with the greatest spirit. 



Eggs. — The usual number of eggs in a complete set of the redstart 

 is 4 but the total ranges from 2 to 5 (I have never found a set con- 

 taining more than 4 eggs) ; this number seems to vary in different 

 sections of its range. J. Claire Wood (1904) reported that out of 

 143 nests with eggs 9 of them had 5 eggs ; other observers have reported 

 finding 5 eggs, but sets of more than 4 eggs are not common. Although 

 the first set generally consists of 4 eggs, if these are destroyed the 

 second set seldom exceeds 3 eggs and very often there may be but 2. 



The eggs are subject to considerable variation in their size and mark- 

 ings; the average short diameter of a series of 50 eggs is 12.3 milli- 

 meters and the average long diameter 16.2 millimeters. They are ovate 

 but some tend toward short ovate. They have a slightly glossy 

 texture with a ground color that varies from white to creamy-white, 

 greenish white, or grayish white. The eggs are speckled, spotted, and 

 frequently blotched with various shades of brown with undertones 

 of gray and drab. There is generally a concentration of markings 

 at the larger end, forming a distinct wreath. The amount and inten- 

 sity of the markings vary ; some eggs may be almost free of markings, 

 on others the markings are so dense as to nearly conceal the ground 

 color. 



Incubation. — ^The period of incubation is 12 days, and is performed 

 entirely by the female. Normally only one brood is reared during 

 any one season. 



B. W. Baker (1944) in 3 hours of observation at a nest during the 

 morning noted that the female left the nest seven times, the length 

 of her absence varying from 2 to 10 minutes, while the time spent on 



