/ 



300 DwiGHT, Plumages of the Scoters. [july 



delayed postjuvenal or a distinct prenuptial moult. The results 

 are the same so far as the plumage is concerned, the new feathers 

 being black in each case, but, if there be a prenuptial moult, three 

 different generations of feathers can be found while as a rule only 

 two are demonstrable. The most developed specimen I have seen 

 (J. D., Jr., No. 4412,0^, April 20), is almost wholly black except the 

 wings and a few scattered brown feathers on the abdomen and the 

 back, but we have no means of knowing how many birds reach this 

 advanced stage — probably very few. The abdomen, as a rule, 

 becomes darker anteriorly and posteriorly as the feather edgings 

 are narrower here and sooner show the dark basal part as they wear 

 off and the fading is considerable. 



Shortly after new feathers appear, the bill of the young male 

 begins to take on the colors of the adult and still more gradually 

 assumes its shape. The colors may closely approximate, by the 

 end of the winter, those of the adult, but the shape is not perfected 

 for at least a year, the swelling of the hump not being marked in the 

 first winter birds although the yellow color may be brilliant. The 

 bill of the female and the legs and feet of the male remain dusky, 

 adults differing very little from young birds. 



No matter how black the plumage maj^ be nor how bright the 

 colors of bill or feet, young males may infallibly be told from adults 

 by the shape of the first primary (Plate XXV) which is not replaced 

 until the first postnuptial moult. The iris in americana is always 

 brown in both sexes at all ages. 



1st Nuptial Plumage. This is either the first winter plumage plus 

 more or less wear, being therefore a mixture of much worn juvenal 

 and less worn first winter feathers, or it is, in part, the result of a 

 first prenuptial moult. It is pretty well established from observa- 

 tions on birds in captivity that no ducks breed until their second 

 year. 



2d Winter Plumage, acquired by a complete first postnuptial 

 moult. It is probable that this moult begins in July, but a lack of 

 specimens prevents me from giving exact dates. A specimen of 

 Dr. L. B. Bishop's (No. 557, August 28) is a male that has nearly 

 completed this moult and acquired the emarginate primary. There 

 are enough worn brown juvenal feathers remaining to show that 

 the bird never had assumed much of the first winter dress. As a 



