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 sufticiently varied by the white or 
bright yeliow 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 
1 First described from New South Wales, 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 South 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. NW. Zeal. ed. 2, 
i. p. 79), it has been met with in considerable numbers 300 miles from land, 
as though in search of new countries to colonize. Yet this author believes it to 
be indigenous to the west coast of the South 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. 
67 
