210 BRITISH BIRDS. 



last Wagtail to arrive, it is the first to leave, most of them having disap- 

 peared by the middle of September. Every meadovr in Holland abounds 

 with these charming little birds, running along the hanks of the dykes or 

 among the grazing cattle, and occasionally perching on the wooden boun- 

 dary-posts, whence they will suddenly take wing to catch a passing fly. 

 But perhaps their beauty is seen to still greater advantage on the marshy 

 banks of the lower Danube, where the brilliant sunshine gilds the deep 

 rich yellow of their breasts as they sit on the top of a willow or tall thistle, 

 or other rank herbage which flourishes in this semi-tropical climate, dis- 

 playing the white outside feathers of their quivering tails as they balance 

 themselves on their uncertain perch. 



The habits of the Blue-headed Wagtail are very similar to those of the 

 other Wagtails. It is partial to swamps, and frequents wet grass-lands, 

 especially meadows containing cattle. In these situations it may be seen 

 running hither and thither, incessantly beating its tail up and down, and 

 feeding in the same manner as the other Wagtails. Its flight is also per- 

 formed in a succession of droops or long curves. 



The song of this bird, like that of its congeners, is scarcely more than 

 a musical twitter. Its common call-note is a chit-up, similar to that of 

 the Yellow Wagtail, but certainly shriller than that of the Pied Wagtail. It 

 has also a prolonged plaintive double note, occasionally heard when the bird 

 is perched. The food of the Blue-headed Wagtail is composed of insects, 

 beetles, small freshwater mollusca, caterpillars, and grubs. 



The Blue-headed Wagtail is a rather late breeder, and its eggs are 

 seldom laid before the middle or latter end of May, often not until the 

 beginning of June, so that probably one brood only is reared in a season. 

 The nest is built on the ground, and is generally well concealed amongst 

 rank herbage. A bank is a favourite situation, beneath a tuft of grass or 

 amongst the gnarled and half-exposed roots of trees standing in open fields. 

 The nest is made of dry grass, rootlets, and scraps of moss, and lined with 

 fine bents, hair, and sometimes a little wool, and more rarely a few feathers. 

 The eggs are from five to six in number, yellowish white or pale bluish 

 white in ground-colour, mottled, spotted, freckled, and clouded with pale 

 brown, and sometimes streaked on the larger end with rich blackish brown. 

 They vary in length from -83 to '73 inch, and in breadth from "59 to 

 •53 inch. Many of the eggs of this bird are absolutely indistinguishable 

 from those of the Yellow Wagtail and the Grey Wagtail. 



The Blue-headed Wagtail often joins flocks of the Yellow Wagtail, and 

 there can be no doubt that the two birds often keep company during 

 winter. The most northern birds generally quit their haunts in August 

 and September, retreating slowly southwards. 



The adult male Blue-headed Wagtail in breeding-plumage resembles the 

 other British Wagtails in the colour of the wings, wing-coverts, and tail. 



