176 U.S. NATIONAL MUSEUM BULLETIN 237 part i 



This description of the adult winter plumage of the male is based 

 on four specimens collected in Illinois during August 1918, three 

 specimens collected during the last week of August 1908 at Mata- 

 moros, Mexico, and one collected at Bolson, Costa Rica, Dec. 

 13, 1909. Two of the Illinois birds are in transitional postnuptial 

 molt, but the others have acquired the complete adult winter plum- 

 age. This plumage is similar to the nuptial plumage, but the entire 

 coloration is very much brighter and the color bands and patches 

 more sharply differentiated. The gray of the pileum and neck of 

 the nuptial plumage is replaced by a rich dark olive-brown ; back snuff 

 brown streaked with black; the rufous of the lesser and middle wing 

 coverts a deep chestnut color; greater wing coverts broadly edged 

 with mikado brown instead of gray; white edgings of the primaries 

 very prominent; the yellow of the breast more extensive anteriorly 

 and posteriorly, even the middle of the belly being tinged with yellow ; 

 the yellow of the breast approaching cadmium yellow; chin tinged 

 with cream color; superciliary and malar stripes hght cadmium; the 

 posterior part of the superciliary stripe light yellow and not white as 

 in nuptial plumage ; the black throat reduced in size and is more or less 

 obscured by pale cream tips of the feathers ; no traces of black on the 

 lower breast; auriculars and flanks plain olive-brown; crissum or 

 under tail coverts warm buff instead of white as in nuptial plumage. 



No females in the adult winter plumage were secured. Dwight 

 (1900) thus describes the female plumages: "The plumages and moults 

 correspond to those of the male. In juvenal plumage females are 

 indistinguishable from males. The first nuptial is acquired by a 

 limited prenuptial moult. In subsequent plumages the throat re- 

 mains pale brown with lateral black chin streaks without the black 

 patch of the male and the colors elsewhere are regularly duller." 

 He gives no detailed description of the adult female winter plumage. 



The abnormal plumages of albinism and melanism are rare in the 

 dickcissel. Of Townsend's bunting (Spiza townsendi (Audubon)), 

 which Cockrum (1952) considered a hybrid between the dickcissel 

 and the blue grosbeak, the 1957 A.O.U. Check-List states: "Known 

 only from the type specimen, taken May 11, 1833, [in Pennsylvania] 

 by John K. Townsend. Its peculiarities cannot be accounted for 

 by hybridism or apparently by individual variation." 



Food. — The following account of the food of the dickcissel is based 

 on the contents of the stomachs and crops of birds collected near 

 Atwood, 111., and on observations made in the field during the nesting 

 season of 1918. The author is indebted to E. R. Kalmbach of the 

 U.S. Biological Survey and to A. N. Caudell of the U.S. Bureau of 

 Entomology for the identification of the stomach contents of 19 of 

 the 33 birds collected. Results of stomach examinations presented 



