ZOSTEROPS. 169 



A male and female shot at Pinetown in July are slightly 

 yellower than a male and female shot at Newcastle in August. 



The yellow on the forehead is occasionally, though rarely, 

 entirely confined to the sides. The breadth of the white eye- 

 ring varies but slightly, excepting in one apparently immature 

 bird which has this ring very narrow. 



In the group of which Z. madagascariensis is the oldest 

 name, there are many nearly allied species, if indeed they 

 really deserve to be treated as such. Believing them all to 

 have come from a fairly recent common stock, it would appear 

 that their colonisation might have proceeded in the following 

 manner, starting from Madagascar as the mother country. 



A party took possession of Africa south of about 27° S. lat. 

 and although scarcely differing in appearance beyond the 

 occasional adoption of a few yellow feathers on the forehead 

 are known as Z. capensis, and one of its members, the type of 

 Z. atmori, Sharpe, has nearly the whole of the forehead yellow. 

 Another, Z. pallida, put on a rather paler dress with sandy 

 rufous flanks and is more readily distinguishable. 



Others on leaving Madagascar by a more northern route, 

 settled in Johanna and Great Comoro Island and became 

 Z. anjuanensis and Z. comorensis, in which the distinguishing 

 character is the yellow sides to the forehead, and some stopped 

 in Aldabra Island, and assuming a yellow shade down the 

 centre of the breast became recognised as Z. aldabrensis ; while 

 those which extended their range into north-east Africa 

 founded a rather large race Z. poliogastra, with the entire 

 forehead bright yellow in adult specimens, and which, with 

 the exception of its slightly larger dimensions agrees exactly 

 in colouring with the type of Z. atmori from Grahamstown. 

 A much better marked, distinct, allied form in north-east 

 Africa is Z. abyssinica, which ranges over the same country 

 as Z. poliogastra. 



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