MOTACILLA ALBA 145 



hind part of crown, nape, throat and upper breast jet-black; back liluish- 

 grey, becoming darker on the rump and upper tail-coverts ; quills blackish- 

 brown, the secondaries and upper wing-coverts broadly margined with 

 white ; tail black, excepting the two outer pairs of feathers, which are pure 

 white, slightly margined with black on the inner webs ; rest of underparts 

 white, washed with grey on the flanks. 



Iris very dark brown ; bill and feet black. 



Total length 7 inches, wing 3-50, culmen -50, tarsus -90. 



Adult female rather smaller than the male and greyer in colouring, and 

 with but little black on the head and throat. 



A winter migrant in Tunisia, this is one of the commonest birds 

 to be met with during that season in the Regency, arriving in autumn 

 and leaving again in spring. Whether any individuals of the species 

 remain to breed in this country, or indeed anywhere in North-west 

 Africa, I cannot say, but there seems to be no authentic record of 

 their doing so. What Motacilla alha algira of de Selys-Longchamps 

 may have been it is difficult to say, but according to Bonaparte (Rev. 

 Zool. 1857, p. 61), de Selys' bn-d resembled M. yarrelli (M. higubris) 

 more than M. alba in having a very dark back, while it approached 

 M. lugens, Pall, or M. leucoptera, Vigors, in having the white on the 

 wings very extended. 



In Algeria and Marocco M. alba is abundant as a winter migrant, 

 but I have no knowledge of the species breeding in either of those 

 countries. 



In Tunisia the White Wagtail is to be found plentifully through- 

 out the country wherever water occurs, and particularly so during 

 the periods of migration. I have notes of its occurrence from most 

 parts of the Regency, and its favourite line of passage is apparently 

 along the east coast down to the Tripoli frontier. 



In its habits the present species resembles its congener, M. lugubris, 

 chiefly frequenting meadows and moist ground, where flies and other 

 winged insects abound. These it catches with wonderful dexterity, 

 its rapid and at the same time graceful movements when thus 

 engaged being well worth watching. On the sea-shore it feeds on 

 small Crustacea and marine insects. Its alarm note is a sharp " tizzick." 

 Though essentially a ground bird, 1 have seen the White Wagtail 

 perching on a bush, and it is also fond of resorting to the roofs of 

 houses and other buildings, particularly in spring, for breeding 

 purposes. 

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