52 



BULLETIN 153, UNITED STATES NATIONAL MUSEUM 



The plumages of this vulture are rather complicated and there is 

 still much to be learned of their sequence and change. A nestling 

 bird in the Museum of Comparative Zoology, from Fashoda, White 

 Nile, is entirely covered with thick white down, except on the loreal 

 areas which are bare. The remiges and their upper coverts, the 

 scapulars, a few feathers of the spinal pteryla, and the rectrices of 

 the Juvenal plumage are just sprouting and are dull earth brown 

 in color. The bill is very high and short, the culmen deeply de- 

 curved, and the nostrils more circular than in adults. No specimens 

 in complete juvenal plumage have been seen, the next stage being 

 represented by birds full grown in size but with the top of the head 

 feathered. These birds differ from adults in that the occiput, crown, 

 and center of the forehead are covered with short, dark fuscous- 

 black feathers, the chin and upper throat are liberally though thinly 

 dotted with short, somewhat shaftless feathers of the same color as 

 the crown; the blackish feathering of the top of the head encircles 

 the ear, and continues dow^n the sides of the neck to the lower part 

 of the throat which is completely clothed with blackish feathers. 

 There is no whitish crop or breast patch in these birds but the black- 

 ish of the lower throat merges into the fuscous brown of the under- 

 parts of the bod3\ 



The next stage is represented by a specimen in the United States 

 National Museum (U.S.N.M. 223196) which resembles the preceding 

 plumage but has the chin and upper throat bare and has the white 

 downy patch on th^ breast. 



