BRITISH GENERAL MIGRATORY MOVEMENTS 595 



which are largely influenced thrushes, finches, larks, lapwings, and golden-plovers may pass 

 westward towards the warmer peninsulas of Lleyn or Cornwall, or they may continue westward 

 to the mild Irish shores. In the same way exceptionally severe weather in northern or north- 

 western Europe will cause a late emigration to our eastern coasts, which frequently takes the 

 form of winter " rushes," which, however, are less extensive in area and numbers than the 

 rushes in autumn. 



Normal migration, whether in autumn or spring, is even-flowing and steady, and in conse- 

 quence not easy to observe. When the travellers are not hurried by adverse weather or by the 

 sudden falls in temperature after a warm but stormy spell, which had held them up at some 

 point of departure, they steadily move towards our shores, along them, or through the country 

 in small parties, and stop to feed wherever food is plentiful. On the east coast in autumn we 

 may look out seawards over a birdless waste of water. A few specks to the east, or more 

 frequently to the north-east, catch the eye, and if we watch these specks we see them growing 

 larger and more distinct. As they approach nearer we distinguish them as birds, then note 

 their particular species some day-migrants, lapwings, skylarks, or grey-crows perhaps. They 

 reach the shore, pass steadily overhead, and alight on some field, often where others of their 

 species have already gathered to feed. Under ordinary conditions they show no sign of fatigue, 

 but now and then a tired straggler is met with, which has hardly power to fly when approached. 

 Many migrants come in during the night or early morning, and it is in the early hours that we 

 may note the changes in the avian population of any particular district caused by the nocturnal 

 immigrants. During the daytime the passage of coasting birds may be noticed. Swallows and 

 martins skim along the shore, snapping up insects here and there, but seldom changing their 

 general southward direction for more than a short diversion to right or left ; lesser blackbacked- 

 gulls stream past over the sea in parties varying in number, or ducks and waders in more or 

 less ordered flocks swing by over the waves. It is only possible to judge that these birds i % e 

 migrating from their constant arrival from the north and movement towards the south. 



When, however, numbers of birds have accumulated at a point of departure, owing to 

 meteorological conditions unfavourable for oversea travel, and some favourable change releases 

 them, there is a hurried departure. It is then that the passage or arrival of hastening migrants 

 is most easily observed ; it is then that migration becomes forced and abnormal ; it is then that 

 the perils of the frail travellers are increased, and many join the great army of the unfit, fall 

 out of the race, and perish. 1 



1 I am indebted to Mr. J. L. Bonhote and Rev. F. C. R. Jourdain for suggeiting a few alterations, especially 

 in the classification of the migrants. [T. A. c.] 



