495 
1921 .] Bird-Migration by the Marking Method. 
Many records o£ this species are available from other 
sources, and these iuclude several curious instances of winter 
movement in a northerly direction. A bird marked as a 
chick in Co. Tyrone was recovered in its first winter in 
Inverness-shire, but others were recorded from Cornwall 
and from Middlesex in their second winters (7). Birds 
marked as chicks in Northumberland reached Argyllshire 
and Forfarshire in their first winters, although another went 
to Ireland and one was recorded from Brittany in its third 
winter (14). Several winter records from the places of 
marking were also obtained during each of these investiga¬ 
tions. Of 33 birds marked as chicks in Co. Sligo 
and subsequently recovered, all, except one from Spain, 
were reported either from the same neighbourhood or 
from within sixty miles at most, the records being almost 
exclusively for the winter months ( 6 ). Witherby (26) has 
also a number of records for this species. 
IV.—HERRING-GULL (Larus argentatus Pontopp.) : 
ANALYSIS OF RECORDS. 
The Herring-Gull is found all the year round in the 
British Isles, immature birds remaining in summer in many 
districts where no suitable breeding-places exist. By purely 
observational means it is not possible to determine the nature 
of the wandering movements that appear to take place in 
winter. 
During the course of the Inquiry, 461 birds of this species 
were marked, 375 of them in the northeast of Scotland. 
Of the latter, 289 were marked as chicks, and 86 as full- 
grown birds caught on the shore at night and mainly in 
September and October 1910, and it is these two categories 
which have provided nearly all the records. The two sets of 
reappearances are treated separately below, as they reveal 
certain differences which are doubtless due to one category 
consisting entirely of native birds while the other may 
contain at least a proportion of winter visitors. 
