192 BRITISH BIRDS. 



Subfamily MOTACILLIN^E, OE WAGTAILS. 



The Wagtails and the Pipits are a group of slender-billed insectivorous 

 birds. The absence of a bastard or first primary sufficiently distinguishes 

 them from the Thrushes, Warblers, Tits, Crows, or Shrikes, and also from 

 the Waxwings and Starlings, in which the bastard primary, though very 

 small, is always present. From the Finches the slender bill is a 

 distinguishing character, and from the Swallows the narrow bill and 

 longer legs separate them sufficiently. 



The Larks, which are probably their nearest allies, differ in having the 

 back of the tarsus scutellated, and in only moulting once in the year. 

 The Wagtails and Pipits have a partial spring moult, which does not, 

 however, extend to the quills and tail-feathers. In both genera the tarsus 

 is scutellated in front. 



The Motacillinse are almost cosmopolitan, and are found throughout the 

 world, except in the Polynesian Subregion, which consists of all the 

 tropical Pacific islands. They are most abundant in the Palaearctic, 

 Ethiopian, and Oriental Regions, and least so in the New World. Only 

 one species of Wagtail enters the New World, in the extreme north-west 

 of the Nearctic Region ; but the Pipits are rather more numerous. There 

 are upwards of eighty species and subspecies in this group of birds, which 

 has been subdivided into numerous genera, many of which are founded 

 upon characters of a more or less trivial nature. Eighteen species are 

 found in the Western Palsearctic Region, fourteen of which are included 

 in the British list. Of these, two have been included on insufficient 

 evidence. 



Genus MOTACILLA. 



The genus Motacilla, as denned by Linnaeus in the twelfth edition of 

 his f Systema Naturae,' vol. i. p. 328, published in 1766, was a very com- 

 prehensive one, including the Robins, the Accentors, the various groups of 

 Warblers, some of the Flycatchers, the Chats, the Wagtails, the Wrens, 



