40 BIRDS OF TUNISIA 



greyer on the crown and nape ; rump and upper tail-coverts white, faintly 

 tinged with buff; upper wing-coverts jet-black; primaries and secondaries 

 brown, the latter broadly tinged with white and buff; tail white at the 

 base, otherwise jet-black ; lores, a narrow line over the eye, ear-coverts, 

 throat and sides of neck jet black ; rest of the underparts white, tinged 

 with buff, particularly on the breast ; axillaries black, tipped with white. 



Iris very dark brown ; bill and feet black. 



Total length 6 inches, wing 3'60, culmen '60, tarsus 1. 



Adult female, spriog, from Gafsa Plain, South Tunisia. 



Upper parts similar to those of the male, but the wings and tail much 

 lighter in colouring, the black pattern being replaced by shades of brown ; 

 underparts buffy-white, the throat and sides of neck rather greyer. 



Soft parts as in the male. 



Total length 580 inches, wing 3-40, culmen -55, tarsus "95. 



Observations. — Some female specimens have the throat and sides of 

 neck blackish, as in immature males. These are probably very old birds. 

 Young males have the black colouring less intense than adults, and the 

 wing-feathers more fringed with white. There does not appear to be much, 

 if any, seasonal change in the plumage of this species, some specimens 

 obtained in winter being identical with those obtained in spring. 



A true desert bird, this Chat has its habitat proper in Tunisia in 

 the more southern districts, where it is resident and non-migratory. 

 The species appears not to occur in the north of the Regency, and 

 no doubt the Saharan chain of mountains forms its natural northern 

 boundary. I, however, possess a specimen obtained at the Sebka 

 of Sidi-el-Hani, not far from Kairouan in Central Tunisia, where a 

 tract of salt-marsh country exists. Here Mr. Aplin met with this 

 Chat when collecting for me in the spring of 1895. As a rule, how- 

 ever, the country north of Gafsa is not suited to the requirements 

 of the species, and its true habitat is to be found in the Chott country, 

 and on the semi-desert plains further south. These districts are 

 indeed typical of the upper Saharan region, being vast stretches of 

 slightly undulating and broken country, extending for many miles 

 and bounded on the north and south by ranges of hills, which 

 decrease in height as one approaches the true desert. The plains 

 here are mostly hard and stony, with a gravel soil, here and there 

 becoming more sandy, and dotted over with dwarf shrubs and low- 

 growing plants. During the winter and early spring, particularly 

 should there happen to have been copious rains, a certain amount 

 of grass and other herbage crops up, and the country then bears a 



