132 



BULLETIN 50, UNITED STATES NATIONAL MUSEUM 



Adult female. — Entire head, back, throat, breast, abdomen, sides, 

 wings, and tail (but not upper and under tail coverts) fuscous, be- 

 coming fuscous-black and black on the nape and top and sides of 

 head and sides of neck; streaked with light buff on the throat and 

 breast: the feathers of the middle abdomen and the upper wing 

 coverts tipped with dull russet, the scapulars, and secondaries nar- 

 rowly tipped with cinnamon buff and mikado brown to avellaneous; 

 upper and under tail coverts, primaries, and rectrices as in male; 

 thighs bright russet barred with fuscous black; soft parts apparently 

 as in male. 



Figure 12. — Rostrkamus sociabilis. 



Suhadult male. — Similar to adult male but with the upperparts 

 tinged with fuscous and the chin, throat, breast, and middle of the 

 abdomen, broadly streaked with cinnamon-buff, the streaks becoming 

 darker and more rufous, almost to deep chestnut on the breast. 



Suhadult female. — Similar to adult female above except that the 

 entire top of the head and the nape are streaked white and black, 

 the individual feathers being white basally and black terminally ;^^ 

 entire underparts whitish to pinlcish buff heavily streaked with 

 fuscous-black; the thighs cinnamon-buff; under wing coverts cinnamon- 

 buff streaked with fuscous-black. 



Juvenal (sexes alike). — Similar to suhadult female but the under- 

 parts more ochraceous-tawny; the under tail coverts washed with 

 buff; above fuscous-black or black; the forehead and anterior part 

 of the crown ochraceous-tawny streaked with black (the tawny 

 becoming more rufescent on the crown) ; cheeks and auriculars pale 

 ochi'aceous-tawny with a broad fuscous band running from the poste- 



" This is also true of the adult, but there the black areas are larger and hide 

 the white. 



