Chtamydera guttata carteri from North West Cape 
digital calipers. Observed differences in some of 
the measured characters between paired 
populations of birds were tested for levels of 
significance with Student's /-test. All skirts of C. 
guttata carteri and several other skins of C. guttata 
from locations about the North West Cape area in 
various museums (see Table 1) were photographed 
under equivalent conditions to enable comparison. 
RESULTS 
As the morphology of the three North West Cape 
specimens of C. guttata in the Museum of Victoria 
collection (HLW 6590, 6591, 6592) and the two in 
the WAM (A8713 collected by Mees and A1224 
collected by Carter) was tine same (and like that of 
the two North West Cape specimens examined 
elsewhere), we first present a composite 
description of these, with comparative reference to 
some other C. guttata specimens held in the 
Museum of Victoria. Following this, we briefly 
comment on the two North West Cape specimens 
held outside Australia: 
The five North West Cape birds held in 
Australian collections differ conspicuously from 
those of the Hamersley Range and the East 
Murchison River area. In the North West Cape 
birds, the chestnut spotting of the blackish nape 
A 
227 
(below the pink nuchal crest) is finer and denser 
than in birds to the immediate east and south-east. 
The chestnut spotting on the lower mantle, back, 
rump and upper tail coverts is also denser (ie. 
there is less black). The pale spots on the mantle of 
the North West Cape birds typically have the 
converging straight edges of the upper half 
meeting in a sharp point at their apex. This is in 
marked contrast to those of birds to the south and 
south-east, in which these spots are typically 
rounded about their upper half as well as the 
lower, the spots being roughly circular or heart- 
shaped overall. Moreover, in North West Cape 
birds the back spotting is uniformly chestnut, 
whereas in the adjacent populations the colour of 
back spotting is variable (chestnut to buff). 
The crown of North West Cape birds is 
conspicuously different from that of birds found to 
the east and the southeast in being much more 
finely spotted (almost streaked on the forecrown) 
chestnut, the black edge of the individual feathers 
being much finer. The result is that the crown in 
North West Cape birds is overall more uniformly 
chestnut than the more variegated and more 
heavily black-marked crowns in adjacent 
populations. There is no silver tipping to the crown 
feathers as is typical of specimens of C. guttata to 
the east and southeast. Ear coverts and throat 
B 
Figure 2 Dorsal (A) and ventral (B) views of Museum of Victoria specimens of Chtamydera guttata from Western 
Australia: three being of C. g. carteri from the North West Cape (upper left), four of C. g. guttata from the 
Hamersley Range (upper right), and four C. g. guttata from the east Murchison River (lower). 
