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breaks from cover and drops again into the flags a short distance 

 beyond. He may hear this again and again, and yet never see a 

 bird, so impenetrable is the thicket of flags. A few vigorous 

 ''squeaks," however, such as frequently draw birds from 

 cover, and the secret is disclosed. A flock of tailless, short- 

 winged birds hovers above his head for a moment, and 

 then is off again into the tangle. If specimens are collected, 

 the disappearance of the Redwings becomes no longer mys- 

 terious. Aside from the loss of the tail, which is obvious, one 

 finds that the outer primary feathers are but just breaking 

 their sheaths. With such handicaps, it is no wonder that the 

 long flights to the uplands are not attempted, and that they 

 seek protection in the effectual shelter of the marsh. The 

 fall disappearance, then, corresponds to that period of the 

 postnuptial molt when the tail feathers and outer primaries 

 are being replaced. Their diet undergoes another change at 

 this time, weevils and lepidopterous larvae again taking the 

 ascendency, for there is but little vegetable food available in 

 the open marsh at this time. 



About the middle of September the adult males again come 

 into evidence, and are seen once more on the uplands by day. 

 They commenced the molt about two weeks earlier than the 

 females and young, and having now completed it, they appear 

 again about two weeks sooner. During the molting period 

 the males and females occurred in mixed flocks, but from now 

 on, with scarce an exception, they are segregated. Shortly 

 the females and immature birds come more into evidence 

 about the borders of the marsh, and by the first of October are 

 as regular in their movements as the males, spending their 

 days on the uplands and coming to the marsh each night to 

 roost. 



Well-defined migration begins about the middle of October. 

 At that time all loitering ceases, and the evening and morning 

 flights in and out of the marsh are very regular, scarcely a bird 

 lingering during the day. Beginning about three-fourths of an 

 hour before, and continuing about half an hour after the sun 

 has disappeared behind the hills, they can be seen in flocks of 

 from ten to a thousand continually dropping into the marsh. 



