100 RECORDS OF THE AUSTRALIAN MUSEUM. 
The distinguishing characters in the seasonal changes of the 
plumage of the under surface of Z. ccerulescens may be briefly 
summarized as follows : — 
Spring plumage. — Throat bright olive-yellow ; chest and breast 
ashy-grey, passing into dull white on the abdomen ; flanks very 
pale tawny-brown; under tail-coverts dull white, in some specimens 
washed with yellow. 
Summer plumage, — Similar to the spring, but the throat 
slightly duller in colour. 
Autumn plumage. — Throat faintly washed with olive-yellow 
or gradually passing into grey ; flanks tawny-buff. 
Winter plumage. — Chin and sides of the throat dull olive- 
yellow ; centre of the throat, the chest, and breast ashy ; flanks, 
deep tawny- buff; abdomen and under tail-coverts dull white, the 
latter in some specimens washed with yellow. 
Transition from ivinter to spring plumage . — Throat greyish- 
white, faintly washed with olive-yellow ; flanks pale tawny-buff ; 
under tail-coverts dull white, slightly tinged with yellow. 
Obs. — The average measurements of examples obtained during 
winter and in summer are alike. All through the year some 
specimens are found with the under tail-coverts tinged or washed 
with yellow. This does not appear to be a sexual character, 
although from the specimens examined the yellowish wash oil 
the under tail-coverts predominates among the males. As a rule, 
however, the dull white or white under tail-coverts are found in 
birds obtained during the winter. 
Under the synonymy of Z . westernensis , Dr. Sharpe includes Z . 
tephropleura , of Could, from Lord Howe Island, but the latter 
species can be readily distinguished from the spring plumage of 
Z. ccerulescens by its bright yellow under tail-coverts, and by its 
larger and more robust bill. At the Macleay Museum I have 
examined the type of Z. ramsayi , described by Mr. George Masters 
from specimens obtained by him on one of the Palm Islands, 
lying north of Halifax Bay, N.E. Queensland. It is a good and dis- 
tinct species, with olive-yellow under tail-coverts, and a broad 
zone of white feathers round the eye. Dr. Sharpe, from the des- 
cription of this species given in the Proceedings of the Linnean 
Society of New South Wales,* considers it probably identical with 
Z. westernensis ; but there is no question that the specific character 
pointed out by Mr. Masters, and the olive-yellow under tail-coverts 
will prevent one when examining this species from confounding 
it with the spring or summer plumage of Z. ccerulescens , or with any 
other Australian member of this genus. 
* Vol. i., p. 50, 
