VIEWS ON MIGRATION. 21 



navia and Africa with great regularity, but in milder 

 climates, as for instance in the British Islands, it 

 is stationary. The Sedge Warbler [Acrocephcdus 

 pliragmitis) is a bird of regular passage, yet many 

 individuals have suffered their migratory impulses 

 to lapse, and reside permanently in parts of North 

 Africa, in Corfu and Crete. The Blackcap {Sylvia 

 atricapilla)^ although a bird of passage with us, and 

 notwithstanding the fact that its migrations extend 

 from about the latitude of the Arctic Circle to with- 

 in some ten degrees of the Equator, is a resident 

 in the basin of the Mediterranean. The dainty 

 little Willow Wren [Phijlloscopus trochilus), one of 

 the most familiar of our summer birds of passage, 

 whose migrations extend from nearly the highest 

 point of continental land in Europe and Western 

 Asia to the southernmost parts of Africa, in a fly- 

 line of nearly 8000 miles, may be taken as one of 

 the very best examples of migration, and yet in this 

 species the habit is by no means universal, and 

 many individuals are resident in North Africa, 

 Spain, and Sicily. Just as remarkable is the 

 ChifFchafl' {Pkylloscopus rufiis) ; in most parts of 

 its range it is a migrant, but many individuals are 

 stationary in Southern Europe. Indeed, a few odd 

 birds have been known to forego migration even 

 in the British Islands and Germany, remaining to 

 winter in the more sheltered parts of those countries. 

 Then the beautiful little Gold crest {Regulus cris- 

 tatus) is only migratory in the colder parts of its 

 range, being, as we know, resident in our islands ; 



