BIRD MIGRATION. 1 5 



2. That the different bands are sufficiently scattered and connected 

 with other bands to form a practically continuous stream of birds is also 

 proved by my experience at Point Lepreaux ; for during nights which were 

 dark or foggy enough to make the lantern attractive, but not sufficiently 

 thick to prevent the birds from continuing their journey after flying about it 

 a few times, there was often not a minute for hours when several birds were 

 not arriving within its circle of light from the east, and an equal number 

 departing towards the west. 



3. That the conditions at Point Lepreaux were not unusual, and that 

 the sky during a night favorable for migration is ordinarily alive with birds, 

 may be learned by anyone having keen hearing who will take the trouble to 

 stand for a few hours on some elevated spot and listen intently. I have 

 done this many times, and at various places, when the faint, lisping notes 

 of Warblers and the louder calls of Thrushes could be heard in every 

 direction and at intervals never exceeding a few seconds. The telescopic 

 observations by Messrs. Scott and Allen, elsewhere alluded to, also furnish 

 valuable evidence, both on this point and on those treated in sections i 

 and 2. 



4. That with most North American birds the majority of adults either 

 precede or accompany the first flights of young in the autumnal migra- 

 tion I am convinced by a long field experience, during which, moreover, 

 I have failed to find any proof that the young of a single species precede the 

 old. My evidence in support of this statement is of two kinds: (i) Ob- 

 servations made on the departure of birds from their breeding stations. 

 (2) Observations on flights arriving from localities north of the stations of 

 observation. The first class of evidence, in my opinion, is much the more 

 reliable, for reasons which will be given presently. It includes a long array 

 of notes, from which I select and condense the following : — 



At all points where I have collected regularly and systematically through 

 July, August, and September, I have found that the adults of most of the 

 smaller land birds which migrate before October, and especially of those 

 which migrate by night, begin to disappear as soon as the young become 

 able to shift for themselves. Their departure is usually gradual, and often 

 scarcely perceptible from day to day ; but before there is any appreciable 

 diminution in the number of young the adults have become so scarce that 

 they commonly represent less than five, and often not more than one per 

 cent of the total number of individuals of their respective species present. 

 As a rule they disappear as soon as, and often before, they have com- 

 pleted their summer moult, whereas the young usually linger for some 

 time after their autumnal plumage is perfected. Every New England col- 

 lector who has paid especial attention to obtaining adult birds in full autumnal 

 dress will testify to the truth of this statement. With the Warblers there is 



