YELLOW-THROATED VIREO 281 



me of the needle of tbe sewing maclnne with its eye at the pointed end. * * * 

 Inside and outside the little heads would reach, with the prettiest turns and cur- 

 vetings imaginable, till, as the nest grew deeper, the work was done more and 

 more from the inside. Then it was gathered together at the bottom, with side 

 joined to side. When this part of the work first took place the nest seemed to be 

 strangely lacking in depth and had an unshapely look altogether. 



But this was the point where the full revelation came to me of how the deepest 

 part is shaped. I saw the bird at this stage inside the nest raise her wings 

 against the upper rim and the twigs which held it and strain with her wings 

 upward and her feet downward till the nest itself grew so thin that I could see 

 thi'ough it in places. Then they began again, for the most part from the inside, 

 weaving in more material to thicken and strengthen sides and bottom where 

 these had become thin and weak through the stretching. This was done many 

 limes over until the proper depth and thickness were both secured. The nest 

 after being stretched out in this way would be like the coarse warp of a fabric 

 on a loom, and into this the little weavers wove their silken threads. 



After this came the embellishing with the bits of lichen. These were brought, 

 and fastened on by means of little filmy threads of the spider drawn from the 

 surface of the nest and fastened down over the moss. 



Samuel A. Grimes has sent me two fine photographs of Florida nests 

 (pi. 33), one in a blaclijack oak and one in a loblolly pine. Nests 

 have been found in other trees than those mentioned above, mostly in 

 various oaks and maples, but also in beech, chestnut, and elm ; prob- 

 ably some other trees could be added to the list. About one week seems 

 to be the average time required to build the nest. 



Eggs. — The yellow -throated vireo lays three to five eggs to a set, 

 usually four. The normal shape is ovate, but some are slightly 

 pointed and some are more oval. They are the handsomest and most 

 heavily marked of any of the eggs of the vireos. The ground color 

 varies from pure white to creamy white or pinkish white, these tints 

 often remaining persistent in the collector's cabinet. They are quite 

 strongly spotted, mostly at the larger end, with various shades of 

 brow^i, reddish brown, chestnut, vinaceous-cinnamon, dark brown, 

 blackish, or dilferent shades of drab or lavender; some of the spots 

 are large enough to be called blotches, even such as occur on king- 

 birds' eggs, but such extremes are very rare; even more rarely, an egg 

 may be nearly, or quite, immaculate. The larger spots often show a 

 washed-out effect around their edges. The measurements of 50 eggs 

 average 20.8 by 14.9 millimeters; the eggs showing the four extremes 

 measure 22.8 by 16.0, 17.9 by 13.0, and 18.8 by 13.2 millimeters. 



Young. — The period of incubation for the yellow-throated vireo 

 seems to be about two weeks, and the young remain in the nest for about 

 the same length of time. Very little study of this subject seems to 

 have been made, but Mr. Hutchins (1902) gives us the following 

 information on it: "After the sitting proper seemed to have begun 

 it was in about two weeks' time that we saw the first signs of life in 

 the nest. The male bird took his part with the female in the incu- 

 bating. He would bring food to her as she sat upon the nest and, I am 



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