6 BULLETIN 19 7, UNITED STATES NATIONAL MUSEUM 



is sufficiently accounted for by the variety of suitable breeding sites 

 they afford. 



The name white wagtail is too firmly established to be altered, but 

 it is a rather absurd misnomer, for the bird has a pied pattern of 

 gray, white, and black. The name is presumably a translation of 

 Linnaeus's "Alba" and has probably been the more readily accepted 

 by English ornithologists because it does serve to express, though 

 in an exaggerated form, the main difference between the black-backed 

 British race or pied wagtail and the paler, gray-backed continental 

 bird. In fact, in this case, as in that of the white rhinoceros, it seems 

 that it must be understood as meaning "not so black" ! 



Courtship. — The courtship display of Motacilla alba seems more 

 elaborate than in most small European passerines. It has been more 

 fully described in the British form or pied wagtail than in the white 

 wagtail proper, but there is no reason to suppose that the races differ 

 in their behavior. The most complete account of the pied wagtail's 

 display is that of Boase (1926). 



In the early stages the female is often pursued hither and thither 

 in a graceful, erratic, dancing flight by one, two, or more males which 

 endeavor to induce her to pause long enough for them to posture 

 before her with the head held high and the bill pointing upward at a 

 sharp angle so as to display the glossy black gorget. It is somewhat 

 curious that according to Boase's observations this display of the 

 throat patch appears not to occur in the display of paired birds, but 

 only in the early stages, of courtship in the narrower sense, when 

 males are endeavoring to attract a mate. Further observation on 

 this point is perhaps desirable. In later stages the male frequently 

 approaches the female in a zigzag course, posturing at the same time. 

 Boase describes two variations of this performance. In one the head 

 was moved with a jerky bowing action, a quick flutter of the wings 

 accompanying each return to the normal position. In the other the 

 bird had the head depressed and carried the wing nearest the female 

 expanded, at the same time expanding and depressing the tail and 

 twisting it over to the same side so as to display as much as possible of 

 its upper surface. Displays of this general type, with variations, 

 are not uncommon. 



Again, as described by Boase, the male may approach the female 

 with wings drooping and tail spread and depressed, head held low, 

 and the feathers of the rump raised, in a manner recalling a display 

 posture of the European blackbird. Boase does not mention coition as 

 following such displays, but the one just described, at any rate, is a 

 typical preliminary to the sexual act. He does, however, describe in 

 this connection another more striking form of posturing in which the 

 male sj^reads and erects the tail vertically, with bill inclined upward 



