ON THE MIGRATION OF BIRDS. 463 
The immigratory movements occurring in NovEMBER are not only on 
a very much reduced scale, but after the middle of the month the immigra- 
tion of such birds as spend the summer in the North entirely ceases, with the 
exception of those of certain marine species (Ducks, Gulls, Grebes, Swans), 
whose late movements to the South are dependent upon severe weather 
conditions.' This is entirely contrary to the views hitherto propounded 
regarding the limits of these movements, but it is, nevertheless, a fact 
well established by this inquiry. 
A few (six only?) northern summer birds which do not breed in 
Britain still occur as immigrants during the earlier days of the month, 
often in considerable numbers. The additions for the month are species 
which only occasionally occur, and whose appearance is in some cases 
indicative of weather influences. A few northern species are recorded 
more numerously during November than earlier in the autumn—namely, 
the Lapland Bunting, the Swans, Ducks generally, the Ringdove, the 
winter Grebes, and the Little Auk, the last, however, irregularly. 
The immigrants hitherto considered are those derived from the north. 
There now remain for treatment those which reach us by a westerly 
movement along the East and West Route, and arrive on the south- 
eastern shores of England. These diurnal movements set in during 
the latter days of Sepremprr, when Larks, ‘Crows’ (Rooks), Tree- 
Sparrows, and some Redbreasts are observed. Immigration increases in 
volume in OcToBER, when, in addition to the species mentioned, Black- 
birds, Thrushes, Grey Crows, Chaffinches, Greenfinches, Goldcrests, 
and, occasionally, Woodcocks are observed. The movements continue 
until the middle of NovemsBer, when they too, during ordinary seasons, 
cease to be observed. They are renewed again, however, on the part 
of Larks, Starlings, Thrushes, and Lapwings on the advent of great 
cold, when the birds chiefly pass westwards along the south coast of 
England. 
During immigration our shores are reached during the late night or 
early morning on the part of migrants from the north. On the contrary 
the immigratory movements from the east, across the narrows of the 
North Sea, appear to be performed during the daytime. 
Autumn Emigration.—It is somewhat difficult to determine what 
species among our British summer visitors are true emigrants during 
Juty. There is no doubt, however, that the departure of adult Cuckoos 
dates from the latter days of the month, when they not only appear on 
the coast-line, but are occasionally killed against the lanterns of the light- 
stations. The Swift is another species that appears with some frequency 
at the stations, which fact indicates that the ebb of its summer sojourn 
in Britain has begun. During the month, especially towards its close, 
there are now and then records of the movements of small numbers 
of * Thrushes, * Blackbirds, * Wheatears, Whinchats, Redstarts, * Red- 
breasts, Whitethroats, Goldcrests, Chiffchaffs, Willow Warblers, Pied 
Wagtails, Grey Wagtails, Meadow Pipits, Swallows, House Martins, 
* On a few occasions during the years of the inquiry sereral Thrushes, Fieldfares, 
Woodcocks, Snipes, and Plovers have been observed in the Orkneys and Shetlands (e.g. 
during the exceptionally severe winters of 1882 and 1886). These may, perhaps, 
have been immigrants, or they may have been birds that.had moved to island-haunts 
from the mainland during the period of great cold. 
* These are the Redwing, Fieldfare, Great Grey Shrike, Brambling, Jack Snipe, 
and Knot. The Snow Brnting also occurs in some numbers. 
