V A Chapter on Wagtails 99 



rather run, instead of hopping, their delicate little 

 legs being often in such swift motion as hardly to be 

 seen as they go ; and all feed chiefly on insects — 

 largely, I think, on minute beetles — and love our 

 British streams and meadows for the never-failing 

 abundance of food they find there. And I should add 

 that in all our three birds the two outer tail-feathers 

 are white, and become conspicuous the moment their 

 owner flies or moves his tail in the familiar way : a 

 characteristic of which I may have something to 

 say later on. 



These are the generic peculiarities of the group, 

 and, as far as I know, they are common to all true 

 Wagtails. But our three British species, though they 

 are alike in so many ways, and are without doubt 

 all descended from a single ancestral type, have 

 developed features which mark them off very clearly 

 from each other. The colouring, for example, is so 

 distinct in the plumage of the adult male birds in 

 breeding dress, as to be recognised at once even by 

 the inexperienced ; and it is interesting to find that 

 they then represent three several types of the world's 

 Wagtails. One is black and white, with a jet-black 

 gorget ; one is yellow and olive-brown, with no black 

 at all ; and the third, which stands between the two, 

 though I take him last in this chapter, is gray above, 

 bright yellow beneath, and has the same black throat 

 ornament as his Pied cousin. Or to put it shortly, 



