^'°''o'^' 1 MiLLIGAN, Some W . Australian and Allied Species. 49 



Specimen (c). — Similar to last preceding except that the 



throat-freckling is in regular crescentic lines. 

 Specimen {d). — Breast pale buff, under wing coverts as 

 in {a). 



Leaving the comparison of the above species, the following 

 plumage phases of the young males of P. occidcntalis may 

 perhaps be interesting : — 



Head. — Brown in fledgling, slate-blue in 6 months and 18 

 months old birds (these age-computations are only approximate, 

 and are based on the assumption that the young bird was hatched 

 in December) ; black in adult. 



Breast, Abdomen, and Under- Tail Coverts. — Impure white in 

 the fledgling, buff in the 6 months old birds, deeper buff in the 

 18 months old birds. (In one of the last-mentioned the breast 

 was pinkish-buff, with yellow patches here and there.) Yellow 

 in adult. 



Secondaries. — Exposed upper surfaces boldly marked reddish- 

 bronze in fledgling and 6 months old birds, blackish-brown with 

 olive-grey margins in the 1 8 months old birds. 



Tail. — In all immature birds a plain uniform brown, with 

 narrow edgings of paler brown in the first two phases, but with 

 olive-grey edgings in the third phase. In mature birds, grey 

 with blackish band. 



From the above it appears that there are three plumage phases 

 at least in the young birds. The last phase is either incomplete 

 or there is a fourth one ; for, although there are, in one skin, 

 evidences of a transition from the pre-mature to the mature in 

 the breast plumage — namely, from pinkish-buff to yellow — 

 there are not any evidences or indications of corresponding 

 changes to the black pectoral band, or the black head, or the 

 white throat or grey tail of the full-plumaged adult. I have field 

 notes (not my own) showing that the sexes breed before assuming 

 full plumage. This trait is not peculiar to the Pachycephalce, for 

 I have similar notes regarding Petrceca goodenovi. The young 

 male, in a general sense, resembles the adult female. The former, 

 however, is readily distinguishable by the presence of an incon- 

 spicuous and concealed tuft of undeveloped yellow feathers at the 

 vent. 



In the course of my examination I was much struck with 

 many variations in the colouration of parts of P . occidentalism 

 which more or less have been relied upon as distinguishing 

 characteristics in allied members of the genus, both Australian 

 and extra-Australian. 



In one skin of an adult male the under tail coverts were almost 

 pure white — one of the two differences urged in the separation 

 of P. glaucura (Gould) from P. gutturalis. In two skins the 

 yellow nuchal collar continued uninterruptedly to the yellow 

 breast, breaking the continuity of the black pectoral band with 

 the black head — characteristics, according to specific descriptions, 

 which are peculiar to at least 1 1 members of the genus, including 



