PIED WAGTAIL 531 



the bark. The nest, which is always well concealed, may be placed 

 either in a hole or in a fissure in the bark of a tree, or behind one of 

 the timbers in the roof of an outbuilding, and is a somewhat rude 

 structure of moss and rootlets intermingled with chips of wood ; feathers 

 being in some instances employed as a lining. In this structure 

 during April or May is laid a clutch of from four to half-a-dozen eggs, 

 which may be one of two types. In the one type the ground- 

 colour is huffish or reddish white, and the spots rufous, with a tendency 

 to collect at the larger end ; in the other phase the ground is nearly 

 pure white, and the colour of the spots varies from reddish to blackish 

 brown, in addition to which there is a deeper layer of obscure violet 

 markings. 



The British tree-creeper {Certhia faniiliaris britminica) differs 

 strikingly from C. fmniliaris typica of Sweden in its rufous brown 

 upper surface, and from C. f. inacrodactyla of central Germany by 

 having the rump, and, in freshly moulted specimens, the whole upper 

 surface more rufous, while the beak, as a rule, is longer. 



The beautiful wall-creeper {Tichodroma murarid) of the mountain- 

 ous districts of central and southern Europe and Asia, is the sole 

 representative of a genus characterised by the soft tail-feathers. In 

 colour the plumage of the upper-parts is grey, but there is a large 

 and conspicuous patch of crimson on the wing. Only four examples 

 of this beautiful bird appear to have been recorded in Great Britain 

 up to the year 1900, namely, one in Norfolk in 1792, a second in 

 Lancashire in 1872, a third in Sussex in 1886, and the fourth in the 

 Channel Islands in 1899. A fifth was taken near Hastings in 1905. 



With the pied wagtail, or "dish-washer" (both 

 Pied Wag-tail . K ^^ • \ ^u r • 1 ■ 



names bearmg allusion to the peculiar jerking 



movements of these birds), we reach the first, 



although not the typical, representative of the family Motacillids, 



which includes not only the wagtails, but likewise their near relatives, 



the titlarks or pipits. The members of both these groups are slenderly 



built, long-tailed birds, adapted for running on the ground, and 



therefore quite unlike the representatives of the three preceding 



families. From all the preceding groups except the Hirundinidai 



(with which, of course, they cannot possibly be confounded) the 



wagtails and titlarks differ by having only nine, in place of ten, 



primary quills in the wing. They are further characterised by the 



beak being comparatively long, slender, and notched, as well as by 



the circumstance that the longest secondary quills reach nearly or 



