216 STUDIES IN lilRD-MIGRATION 



favourably situated station in the North Sea, I, on 

 several occasions between i8th September and 19th 

 October, observed and captured Song-Thrushes at the 

 lantern between the hours of midnight and 4 a.m. On 

 each of these occasions they occurred with such species 

 as Redstarts, Pied Flycatchers, Mistle - Thrushes, 

 Blackbirds, Meadow- Pipits, Wheatears, Starlings, Sky- 

 larks, Chaffinches, Rooks, and Jackdaws. All these 

 may have been of Central European origin, and it 

 is most significant that I never saw this bird in 

 company with any of the species with which the 

 northern Thrushes invariably arrive on our shores — a 

 fact which has led me to conclude that the visitors 

 at the Kentish Knock arrived there from the east. As 

 yet, I have no information relating to the return spring 

 passage of the Song-Thrush, nor of some other species 

 which certainly traverse this line of flight in the autumn, 

 and doubtless do so in the spring also. 



Winter Movements. — The great emigratory move- 

 ments of the winter sometimes commence in November,^ 

 and are continued during December, January, and 

 February." They are synchronous with outbursts of 

 cold, of snow, or of extremely unsettled weather. Such 

 untoward conditions may prevail generally over our 

 islands, or they may be circumscribed ; and their in- 

 fluence on the emigrations of the Thrush is in direct 

 consonance with the distribution of the disturbing 

 elements. 



1 In 1886, as early as 4th and 6th October, there were great emigratory 

 movements on all our coasts, due to extremely unsettled weather, with 

 thunder in the north and north-west, accompanied on the 5th by a great 

 change of temperature — a fall of fifteen degrees below that of the previous day. 



- There are also movements during March in some years ; but they are 

 of a local nature, and are not to be regarded as emigratory. 



