582 BULLETIN 2 03, UNITED STATES NATIONAL MUSEUM 



identical with some song sparrows' nests." Another nest, found on 

 March 27, was in a similar situation but was only half as high. And 

 a third was found on March 28, "in a heavy growth of 'cat-tails' near 

 the outer edge of the clump, and placed one and one-half metres high. 

 This nest, like the others, is composed of 'cat-tail' leaves, but is 

 lined almost exclusively with black horsehairs, so few being used that 

 they do not even hide the structural material." It should be noted 

 that the birds breeding near Comondu are somewhat intermediate 

 between the two races, but, as we have no nesting information from the 

 Cape region, it seems best to include these quotations here. 



Eggs. — Two or three eggs seem to make up the set for Belding's 

 yellowthroat ; 3 seems to be the commonest number. The 12 eggs in 

 the Thayer collection are ovate and slightly glossy. The ground color 

 is white or creamy white, which is rather sparingly speckled, spotted 

 or blotched with "light vinaceous-drab," "light mouse gray," "pale 

 brownish drab," or "Quaker drab," with fewer spots of "Hay's brown," 

 "Dresden brown," or black. The markings are generally concentrated 

 at the large end, often leaving the small end immaculate. The wreath, 

 which may be made up of fine, dense specklings or spots, often has 

 over-writings of black which circle the ^gg. The measurements of 

 32 eggs of the species, some of which may be intermediate between the 

 two races, average 19.5 by 15.0 millimeters; the eggs showing the 

 four extremes measure 21.0 by 16.0, 18.0 by 14.5, and 20.1 by 14.0 milli- 

 meters (Harris). 



Plwnages. — Brewster's fine series probably illustrates all the regu- 

 lar plumages of this yellowthroat. He (1902) describes the juvenal 

 plumage from a specimen taken on September 5, just before the post- 

 juvenal molt, as follows: "Above dull brownish drab, the wings 

 faintly, the tail distinctly, tinged with olive ; greater and middle wing 

 coverts edged and tipped with rusty, forming obscure wing bands; 

 below pale brownish buff, deej^est on the sides, abdomen, and upper 

 portion of the breast, unmixed with yellow save on the chin, where 

 there are a few bright yellow feathers, evidently those of the first 

 winter plumage; bend of wing slightly yellowish; under surface of 

 wing ashy white ; lores with a faint yellowish tinge." 



This and other specimens indicate that the postjuvenal molt of the 

 body plumage and the wing coverts occurs in late August and Septem- 

 ber. The male in first winter plumage differs from the adult "only 

 in having the feathers of the black mask slightly tipped with grayish 

 or yellowish, especially on the forehead; the yellow border of the 

 mask more restricted and mixed with brownish ; the breast and under 

 tail coverts tinged with brownish saffron; the flanks and sides rich 

 purplish cinnamon." The female in first winter plumage differs from 

 the adult female in autumn "only in having the upper parts tinged 



