134 BRITISH BIRDS. 



Dieppe, and occurs regularly as a mig*rant tliroug'h 

 Portugal and the western half of the Spanish Peninsula. 



In winter it is found over a large part of the continent 

 of Africa and has even reached the Transvaal, but it is of 

 most frequent occurrence along the west coast. 



The nesting habits of this bird are given more or less 

 fully in all the text books, and are so well known to 

 British ornithologists that there is no need to recapi- 

 tulate them here. 



On the continent of Europe our common species is 

 replaced by one or other of the numerous forms of the 

 Blue-headed Wagtail, the males of which all differ from 

 the males of the Yellow Wagtail in having the head of a 

 lighter or darker shade of bluish-grey instead of greenish- 

 yellow, and having a white streak above the eye (absent 

 in some of the forms) instead of a broad streak of canary- 

 yellow. The females and young birds are less easily dis- 

 tinguished. These various forms are only separable from 

 one another by the differences in shade of the colour of 

 the head and the j)i*esence or absence of the white eye- 

 stripe. Of these forms the following five have occurred 

 in this country : 



1. Blue-headed Wagtail. MotaciUa flava flava L. 



The Blue-headed Wagtail is found over the greater part 

 of Europe, ranging from as far north as central Scandi- 

 navia and northern Siberia, to the shores of the Mediter- 

 ranean. The adult male has a bluish-slate crown, a white 

 stripe above the eye, and nearly always an ill-delined white 

 streak through the ear-coverts, which are darker than the 

 crown. The female can be distinguished from that of 

 M. raii by the slightly bluer tint of the crown and the 

 purer whiteness of the eye-stripe and chin. The young 

 birds in autumn are much less easy to identify with 

 certainty, especially in the field. In the latter part of 

 August, and from thence on till the beginning of October, 

 when they are to be found on our coasts, the autumn 

 moult is taking place, and being a gradual process, a good 

 deal of variation is to be met with according to the ages 

 of the individuals and the consequent different degree to 



