CHANGES IN PLUMAGE OF ZOSTEROPS OERULESOENS — NORTH. 99 
collected or sent me for examination has prepared a series of 
nearly fifty skins in every stage of plumage. The result of my 
observations conclusively prove that the Z % westernensis of Quoy 
avid Gaimard, the type of which was obtained by them at Western 
Port, Victoria, is only the spring and summer attire of Z. ccerules - 
cens Latham. Taking the two extreme phases of winter and 
summer plumage exhibited in Z. ccerulescens , it can be easily 
understood why each phase should be thought to belong to a 
distinct species ) and it is only where one has these birds under 
daily observation, and obtains specimens during every month of 
the year that the intermediate stage, or the gradual transition of 
one phase of plumage to the other, is observed. These changes 
in the plumage of Z. ccerulescens have already been pointed out 
by me in a series of skins exhibited in August last at a meeting 
of the Linnean Society of New South Wales, Typical examples 
of Latham’s Z. ccerulescens ■,* with the deep tawny-buff Hanks and 
grey throat, the autumn and winter attire of this species, may be 
obtained in the neighbourhood of Sydney from the middle of 
April until the end of August. Some specimens, however, are to 
be found during April that have not quite lost their summer 
plumage, and in August others that have already began to attain 
their spring livery ; these birds have the yellow throat more or 
less clearly defined. Usually the first indications of losing the 
deep tawny-buff flanks and acquiring the yellow throat are seen 
during a normal winter, about the second week in August, in 
some seasons a fortnight earlier, but in two specimens examined 
the grey throat was retained as late as the 19th September. 
During August and September, however, the gradual transition 
from the winter to the spring attire (the Z. westernensis of Quoy 
and Gaimard),f is slowly taking place, and by the middle of 
October not a bird is to be seen with the deep tawny-buff flanks 
and the grey throat. Specimens shot in November have the 
throats of a brighter olive-yellow than at any other period of the 
year ■ the flanks at that time being of a very pale tawny-brown. 
At mid-summer, when the breeding season with the species is 
virtually over, the throat is slightly paler than in the spring, and 
this livery is retained until the beginning of March. The flanks 
then become darker, increasing in intensity of colour from that 
time forward, the yellow feathers on the throat also disappearing 
and passing into grey until the autumn livery is again fully 
assumed by the end of April. 
Of six specimens obtained at Table Cape, Tasmania, during 
April, 1894, three have the throat grey, the remainder faintly 
washed with yellow, and in all of them the flanks are of a deeper 
tawny-bulf than in Australian examples. 
* Z. dorsalis (Gould), Eds. of Aust., iv., p. 81, 
f Voy. de l’Astrolabe, pi. 11, fig. 4, 
