PASSERINE BIRDS OF NEW YORK 157 



Similar to the previous plumage, but darker above and yellower below, a rich ochre 

 or maize yellow prevailing, palest on chin and abdomen, the sides of the breast 

 and flanks and under tail coverts conspicuously streaked with dull black veiled 

 by the overlapping feather edges. 



The relative size of the feathers of this plumage and their 

 pattern is shown on plate I, where the feathers of a September 

 male are figured. They have been reproduced much darker 

 than their pale brown color would indicate. There is some 

 variation in the distribution of the black pattern of lateral feath- 

 ers of the ventral tract in young birds and this may be seen 

 on plate I, figs. 1-6, 19-22. 



4. First Nuptial Plumage acquired by a complete pre- 

 nuptial moult. 



Plumage almost wholly black, the body plumage veiled by long maize-yellow feather 

 tips. The nape is rich ochre and the scapularies white, the inner plumbeous, 

 both edged with olive-gray. The outer primary is edged with white, the two 

 adjacent with maize-yellow, the tertiaries, greater coverts and interscapularies 

 with wood-brown. Rump plumbeous, upper tail coverts white, both areas 

 veiled with olive-gray or olive-buff. Tail tipped with olive -gray. Bill black. 



The terminal inch of the webs of the outer primaries is paler 

 as if the black color had not extended so far, but the borders 

 are, in May, less abraided than are many of these feathers when 

 the birds pass southward in September. It would be safe to 

 assume a prenuptial moult of the Bobolink from this fact alone 

 and a bird taken March i, i886 (Amer. Mus. Nat. Hist., No. 

 32783), near Corumba, Brazil, on the Bolivian boundar).', proves 

 it, although this specimen is doubtless an adult. I have also 

 seen several caged birds which have undergone a complete moult 

 in the early summer. Spring birds reach New York about two 

 months after this moult and the fugaceous yellowish feather tips 

 have so worn away (see plate I, figs. 23-25, 28, 29) that the 

 specimens are chiefly black, white and buff, except on the abdo- 

 men, flanks and under tail coverts where the tips persist longest. 



5. Adult Winter Plumage acquired by a complete post- 

 nuptial moult beginning the end of July. Similar to first winter 

 plumage, usually whiter below especially on the chin and middle 

 of the abdomen, and above with richer brown edgings especially 

 of the tertiaries. The bill becomes clay colored or purplish. The 



