14 MEMOIRS OF TJIE NUTTALL ORNITHOLOGICAL CLUB. 



leaders are naturally followed by all the members of their own particular 

 species. I believe further that the southern extremity of the AUeghanies 

 is the chief point of departure in the Eastern United States. 



It may be further objected that the adults of many, or, as I believe, all 

 species migrate southward first, and often several weeks in advance of the 

 young. It is perfectly true, nevertheless, that a few old birds are always to 

 be found in the larger flights, although the latest of these are certainly 

 composed mainly of young. The two facts taken in connection, however, 

 seem to me to strengthen rather than weaken the conclusions just advanced, 

 for it is evident on the one hand that many of the smaller parties must be 

 entirely without experienced leaders, and equally clear on the other, that a 

 few such guides must always mingle in the armies which these parties col- 

 lectively form. 



Another possible objection which has occurred to me is that the flood tide 

 of migration is preceded, as well as closed, by more or less local or limited 

 movements, during which the birds at any one time on the wing must be too 

 few and scattered to constitute an uninterrupted stream. How then do they 

 lind their way? It may be answered that the earlier flights can have no 

 ditliculty, for, as already stated, they are made up chiefly, if not wholly, of 

 old birds, who, being familiar with the route, are independent. With the 

 closing flights there is more trouble, for these, as we have also seen, are 

 composed chiefly, and in some cases entirely, of young. But is it necessary 

 to assume that such tardy travellers* often reach their southern destination, 

 unless fortuitously and after long wanderings? Are they not much more 

 likely to perish of cold or hunger, or to furnish some of the many recorded 

 cases of exceptional wintering or other unusual occurrence? As far as I 

 have seen, accidental visitors to Massachusetts, almost without exception, 

 are young birds, and the majority also are taken ver}' late in autumn, — 

 facts of obvious significance in this connection. 



During the preceding argument I have assumed several facts which are 

 so essential to my conclusions that I find it necessary to give, at least briefly, 

 the evidence on which they rest. It is as follows : — 



I. That these birds migrate either singly or in straggling bands is 

 shown by the fact that at Point Lepreaux they invariably arrived at the 

 lantern in this order and never in compact flocks. Less conclusive but 

 more familiar testimony is the fact that they are always seen by daylight 

 either in loose, scattered parties or singly, and never in flocks, such, for 

 instance, as are formed by Bobolinks and Blackbirds. 



* I have repeatedly noticed that late stragglers are apt to be found in company with species 

 with which they do not usually associate. Hence it is probable that they often avail themselves 

 of the companionship and guidance of any birds which may be passing at the time. 



