98 Scott on the Migration of Birds. 



shown the moon, then a few days past its full phase. While 

 viewing this object my attention was at once arrested by numbers 

 of small birds more or less plainly seen passing across the field 

 of observation. They were in many cases very clearly defined 

 against the bright background ; the movements of the wings were 

 plainly to be seen, as well as the entire action of flight. In the 

 same way the shape of the head and the tail were conspicuous, 

 when the bird was well focused. As the moon had not been very 

 long above the horizon the direction of observation was con- 

 sequentlv toward the east, and the majority of the birds observed 

 were fiving almost at right angles to the direction in which the 

 glass was pointed. 



Here then was opportunity for the determination of two 

 points — the kind of birds that were flying and the general direc- 

 tion in which they were moving. Respecting the first, it was 

 comparatively easy to decide as to what families the species 

 belonged. This point was gained by observing the general shape 

 of the birds, their relative size, the motion of their wings, and 

 their manner of flying ; that is whether the flight was direct or 

 undulating, by continuous strokes of the wings or by an intermit- 

 tent motion of those members. 



Most of the birds seen wen- the smaller land birds, among 

 which were plainly recognized Warblers, Finches, Woodpeckers. 

 and Blackbirds; the relative numbers being in the order of kinds 

 above named. Among the Finches I would particularly mention 

 Chrysomitris tristis, which has a very characteristic flight ; and 

 the Blackbirds were conspicuous by the peculiar shape of the 

 tail, from which characteristic I feel most positive in my identifi- 

 cation of §)uiscalus purpureas. I mention such details to ex- 

 plain just how observations were made and conclusions arrived at. 



In regard to the second point, with rare exceptions the birds 

 were found to be flving from northwest to southeast. I do not 

 mean that this was absolutely the direction but that it was the 

 approximate and general one. 



It is not within the scope of the present paper to do more 

 than give details on two other points, namely, the estimated num- 

 ber of birds passing through a given space during a given time 

 and the height at which the birds were most abundant. For the 

 basis of the first of these points it was necessary to note, first, how 

 many birds passed through the field of observation per minute, 



