ON THE MIGRATION OF BIRDS. 467 
others are more abundantly recorded than hitherto. There are also con- 
siderable arrivals of Wheatears, Warblers, Swallows, and Sandpipers and 
Plovers of various species, on our southern coast quite down to the end 
of the month, some of their movements being very marked. These are 
undoubtedly birds. of passage, on their way to northern summer haunts 
beyond the limits of the British Isles, for our own birds of the same species 
are then busily engaged in incubation or tending their young. 
During the first half of JuNE several species whose breeding range 
extends to the Polar regions,appear in considerable numbers on our shores 
on their way to the far north ; a few appear even still later. The chief 
among these late birds of passage are the Grey Plover and the Knot, and 
less numerously or less frequently the Snow Bunting, Wigeon, Barnacle 
Goose, ‘Grey Geese,’ Swans, the Dotterel, Turnstone, Sanderling, Ruff, 
Bar-tailed Godwit, Whimbrel, and a few Great Northern Divers.! 
In connection with the spring immigration it has to be remarked that 
the observations are all in favour of the theory that the earliest arrivals 
among the summer visitors to our Islands are British-breeding birds. 
This is borne out by the fact, well known to all field-naturalists, that our 
summer birds appear in their breeding hawnts in our islands immediately 
after their first appearance on our coasts in the spring. Additional proof 
is furnished by the fact that summer birds arrive in Britain at earlier 
dates than in Heligoland, where nearly all the species observed are en 
voute for more northern lands than ours. The further fact already men- 
tioned, that down to the end of May, and in some instances the first half of 
June, large numbers of birds of species which are summer visitants to 
Britain, arrive on and pass along our coast as birds of passage, proves that 
the migrants bound for the north are the last of their kind to appear in 
the British area. 
Spring Emigration.—The spring emigration from the British Isles to. 
continental Europe sets in on the part of certain species early in the year, 
indeed before the winter emigratory movements have ceased to take place. 
Thus in FEBRUARY, in some seasons, ‘Geese’ are recorded as moving 
northwards in considerable numbers. The chief emigratory movements 
of this month, however, are the departure of Larks and Rooks along the 
‘East and West Route’ to the Continent. These take place in some years 
during the early days of the month, and are observed on the south-east 
eoast of England—chiefly at the lightships off the coasts of Essex and 
Kent—where the birds observed are proceeding in a south-easterly and 
easterly direction across the North Sea, returning by the same lines of 
flight as those along which they travelled to our shores in the autumn. 
During Marcu these south-easterly movements become more pro- 
nounced, and the emigrants include the Hooded Crow, Rook, and 
Skylark. Emigration for the north also commences, and the following 
winter visitors are recorded as leaving our Islands during’ the month : 
Great Grey Shrike, Shore Lark, Swans, ‘ Wild. Geese,’ Gadwall, Scaup, 
Golden-eye, Long-tailed Duck, Red-throated Diver, and probably many 
others. In March, too, certain species (Greenfinch, Chaffinch, Twite), 
which regularly seek the islands off the west coast of Ireland as winter 
retreats, are mentioned as taking their departure for the summer. 
' The fact that these birds, or most of them, should arrive on our shores as birds 
of passage thus late in the migratory season, lends some countenance to the theory 
that the birds of certain species going furthest north in summer go the furthest south 
for winter quarters, 
bw 
HH 
