THE AUK : 



A QUARTERLY JOURNAL OF 



ORNITHOLOGY. 

 vol. x. October, 1893. no. 4. 



ON THE CHANGES OF PLUMAGE IN THE BOBO- 

 LINK {DOLICHONTX ORTZIVORUS). 



BY FRANK M. CHAPMAN. 



In a previous number of 'The Auk,' 1 I described, under the 

 above title, the changes which occur in the plumage of the Bobo- 

 link, with particular reference to the manner in which the breeding 

 plumage of the male is acquired. This latter point was one on 

 which considerable difference of opinion existed, but the question 

 seemed to be settled by a specimen in the American Museum of 

 Natural History (No. 32,783, H. H. Smith, Corumba, Matto 

 Grosso, Brazil, March 1, 18S6) which showed clearly the charac- 

 ter of the spring change of plumage. 



This specimen is apparently unique and exhibits in a remark- 

 able degree the extent of a change in color which, in a compara- 

 tively short time, occurs solely through fading and a wearing 

 away of the exposed tips of many of the feathers. 



When compared with a specimen in which, through these 

 causes, the 'full' or black plumage has been acquired the differ- 

 ences are so great that it is difficult to believe they can have 

 occurred without an actual moult. For this reason the Editors of 

 'The Auk' have decided to figure the Corumba specimen and 



1 Vol. VII, 1890, pp. 120-124. 



