ZOSTEROPS 1057 



The birds of this group are mostly of unpretending appearance, 

 the plumage above being generally either mouse -coloured or 

 greenish-olive ; but some are sufficiently varied by the white or 

 bright yellow of their throat, breast or lower parts, and several 

 have the flanks of a more or less lively bay, while, as the annexed 

 figures shew, the bill often differs in form. It is remarkable 

 that several islands are inhabited by two distinct species, one 

 belonging to the brown and the other to the green section, the 

 former being wholly insular. The greater number of forms seem 

 to be confined to single islands, often of very small area, but others 

 have a very wide distribution, and much interest has been excited 

 by the undoubted fact that the type-species, Z. cxrulescens, has of 

 late years largely extended its range. ^ 



All the species of Zosterops are sociable, consorting in large 

 flocks, which only separate on the approach of the pairing season. 

 They build nests, described as being variously placed — sometimes 

 suspended from a horizontal fork and sometimes fixed in an upright 

 crotch — and lay (so far as is known) pale blue, spotless eggs, 

 thereby differing wholly from several of the groups of birds to 

 which they have been thought allied. Though mainly insectivorous, 

 the birds of this genus will eat fruits of various kinds, and in such 

 quantities as to be at times injurious. The habits of Z. cxrulescens are 

 well described by Sir W. Buller, and those of a species peculiar to 

 Ceylon, Z. ceylonensis, by Col. Legge {B. Ceylon, p. 586), while those 

 of the widely-ranging Indian Z. palpebrosa and of the South- African 



^ First described from Ncav South AVales, where it is very plentiful, it had 

 been long known to inhabit all the eastern part of Australia. In 1856 it was 

 noticed by naturalists as occurring in the Soiith Island of New Zealand, when 

 it became known to the Maories by a name signifying ' ' Stranger, " and to the 

 English settlers as the "Blight-bird," from its clearing the fruit-trees of a 

 blight by which they had lately been affected. It soon after appeared in the 

 North Island, where it speedily became common, and it has thence spread not 

 only to the Chatham Islands, but, as Sir W. Buller states {B. N. Zeal. ed. 2, 

 i. p. 79), it has been met with in considerable numbers 300 miles from laud, 

 as though in search of new countries to colonize. Yet this author believes it to 

 be indigenous to the west coast of the Soutli Island, and Sir James Hector 

 joins in that opinion. If they be right, it is, however, pretty certain that 

 until the year before mentioned it must have been confined to an extremely 

 small district, and the only assignable cause of its spreading so rapidly, when 

 it did extend its range, is that of a large surplus population unable to find a 

 living at home. It is known to propagate at a high rate of increase, and at 

 times numbers have been found dead, apparently for want of food. In any 

 case it is obvious that this Zosterops must be a comparatively modern settler 

 in New Zealand, though Sir W. Buller says that he and Mr. Gould were able 

 to pick out New Zealand examples from a series otherwise made up of Australian 

 specimens. Hence it would seem as if a slight amount of differentiation had 

 been set up ; but the variation would doubtless have been greater had the species 

 been an ancient colonist. 



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