2 2 THE MIGRATION OF BIRDS. 



but its numbers are increased in autumn by indi- 

 viduals from far across the sea. The Hooded 

 Crow {Corvus comix) is yet another instance of 

 modified migration. In Scotland this bird is 

 sedentary, elsewhere it is one of the most regular of 

 migrants ; vast numbers, for instance, coming to the 

 eastern districts of England in autumn and return- 

 ing in spring. Even the Magpie {Pica caudata) 

 is a migrant in the northern and colder portions of 

 its range. The Reed Bunting (Emberiza schceniclus) 

 and the Common Bunting {Emberiza miliaria) are 

 both examples of species in which many individuals 

 are of regular migratory habits, whilst others are 

 practically resident. Such a sedentary species as 

 the Yellow Bunting {Emberiza citrine/la) is in this 

 country, is a regular migrant from the Arctic 

 regions, retiring in winter to the South of Europe, 

 Asia Minor, North-western Persia, and North- 

 western Turkestan. The Ring Dove {Columba 

 palumbus) is a regular bird of passage in the 

 northern portions of its range, passing Heligoland 

 in large numbers every autumn, and less abundantly 

 in spring. Such a well-known migrant as the Corn 

 Crake {Crex pratensis) is almost everywhere a bird 

 of passage; but in Algeria, Palestine, and Asia 

 Minor it is sedentary. The well-known Oyster- 

 catcher {Ho'matopus ostralegus) is a resident on the 

 British coasts, but the individuals spending the 

 summer on the coasts of Arctic Europe and the 

 Baltic Sea are birds of regular passage to Africa. 

 In the same manner the Little Ringed Plover 



