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earliest of birds throughout their summer area, reaching th^ 

 British Islands during the last week in March, but are amongst 

 quite the last migrants to leave in the autumn. Whereas the- 

 swift and red backed shrike arrive very late in spring, not before 

 May here, and are amongst the first to travel south in the autumn. 

 The number of some birds seen migrating in the autumn is almost 

 incredible. The little bustard crosses the Caucassian Steppes in- 

 millions. Flights of skylarks cross certam points in a scarcely 

 broken stream for days and nights together. Prjevalski observed 

 the needle-tailed swift in autumn passage in Mongolia passing 

 overhead for an entire day almost without cessation. 



The British Islands are admirably situated for observing 

 migration. They are the summer quarters of vast numbers of 

 birds, the winter home of others, and are situated on the direct 

 fly-line of many that pass over them to breed further north, and 

 return over them in the autumn to winter further south, only 

 staying for a few days on each journey, and being true " birds of 

 passage " for us. They are visited by birds that fly north during 

 the winter of the Antipodes, by birds that come from the far East^ 

 and not a few from America. Many rare birds that have taken an 

 abnormal flight are also found on them. Many of the British 

 migration reports read like romance. " Birds striking the lights ; 

 birds in countless hosts, drifting by in feathery tides ; birds in 

 hundreds exhausted and falling into the sea to perish, or allowing 

 themselves to be taken by the hand ; birds passing for days 

 together, hterally square miles of them ; birds by day and birds 

 by night, flying in regular steady waves or in bewildering rushes r 

 birds following the rays of revolving lamps, or hurling themselves- 

 against the dazzling beacons to die, or settling in crowds to rest!'* 

 The most important highways of migration in the British Islands- 

 are always the coast lines, especially along the east and south 

 coasts, draining a considerable migration from Scandinavia by way 

 of the Shetlands and Orkneys. Land birds skip most of the great 

 indentation of the coast, flying from one headland to another. 

 The valleys leading from the Humber and the Wash are favourite 

 routes to the interior. The goldcrests, that come in autumn 

 sometimes in great rushes, may be traced up the valleys of the 

 Don, and Sheaf, and Trent, almost to their sources. The song- 

 thrush and various waders and crows follow a similar course. 

 Birds seem to prefer entering and leaving a country by a low-lying- 

 coast, and not by high cliffs. The Dart valley is a favourite route 

 for cuckoos, warblers, redstarts, and flycatchers, returning in spring. 

 The commencement of migration in the British Islands is most 

 noticeable in February, when various birds that have been winter- 

 ing here begin to pass towards the continent, especially blackbirds^. 



