T.IO Chapman, Changes of Plumage in the Bobolink. |Oct 



with it a bird taken later in the season (Am. Mus. No. 36,182, 

 Rutland, Vt., Jenness Richardson, June 4, 1SS9) in order that 

 the two may be readily compared. At their request I repeat 

 here as briefly as possible the substance of my former paper. 



In the course of one year the male Bobolink passes through the 

 following phases of plumage : Late in July or early in August 

 when the breeding season is over, the black male, similar to the 

 figure in the background of the accompanying plate, undergoes a 

 complete moult and appears in the yellowish, Sparrow-like 

 plumage of the Reed-bird, which closely resembles the plumage 

 of the breeding female. In this costume the birds migrate 

 southward, pausing en route to visit the rice-fields of the South, 

 and apparently continuing their journey to the campo districts of 

 southwestern Brazil. 



The Corumba specimen shows that the spring change of 

 plumage occurs by March 1. As before stated considerable 

 difference of opinion existed as to the nature of this change, but it 

 was generally believed that the yellowish Reed-bird became the 

 black Bobolink not by moulting but by a change in the color of 

 the feathers. That is, the black area which is present at the base 

 of some contour feathers was supposed to gradually increase in 

 size, while at the same time the tips of the feathers became worn 

 away. As for the buffy nuchal patch and whitish scapulars and 

 rump, I do not know that the manner of their acquisition had ever 

 been explained until the Corumba specimen was described. 



This specimen shows that in the spring as well as after the 

 breeding season a complete moult takes place. As a result of 

 this moult the bird gains a plumage very similar to that shown 

 by the figure in the foreground of the plate. 



The Smith specimen is not quite so far advanced as this figure 

 shows; the centre of the belly, the first primary and several of the 

 secondaries in both wings belong to the old, or Reed-bird plumage, 

 while the tail is but one third grown. In drawing this bird Mr. 

 Thompson completed the moult of the wings and tail but did not 

 equally alter the centre of the belly, which should be of the same 

 color as the breast. 



The change which follows is one that occurs in many birds, but 

 in none with which I am familiar is it so marked as in the Bobo- 

 link There is a series of birds in the American Museum which 



