EXISTING SPECIES OF THE GENUS PHASCOLOMYS. 
larger Island specimens, of course, approximate in size to the smaller 
Tasmanian ones, just as the larger Tasmanian ones do to the smaller 
P. mitchelli. In the case of the Tasmanian form, one skull, for 
which we are indebted to Mr. H. H. Scott, curator of the Launceston 
Museum, is remarkable for its relatively large size. Its basal length 
is 163 mm., the next largest being 151 mm., but even this largest 
Tasmanian skull is slightly smaller in size than the smallest P. mit- 
chelli, and it stands out as a giant amongst the Tasmanian specimens. 
When other bones, such as the humerus and femur of the Island 
species (Plate 11, Figs. 9-14) are seen side by side with those of the 
Tasmanian form, the difference in size and in robustness of the bones 
is very marked, and they clearly indicate two animals of very dif- 
ferent form. 
The measurements of both the upper and lower tooth series serve 
also to mark the Island species as distinct. The maximum length 
of the upper tooth series of the Island species is 45 mm., the mini- 
mum of the Tasmanian species being 47 mm., and that of P. mitchelli 
50mm. The maximum of the lower tooth series of the Island species 
is 46 mm.; the minimum of the Tasmanian form is 48 mm., and 
that of P. mitchelli 52 mm. 
A reference to Plate 11, Figs. 1 and 2, illustrating respectively 
side views of the skulls of a King Island and Tasmanian wombat, 
serve to show not only the difference in size, but one or two features 
of structural importance in which they differ from one another. In 
the Tasmanian specimen (and the same is true of P. mitchelli) the 
paroccipital process slants downwards and markedly forwards, in the 
King Island skulls it always runs nearly straight down, the forward 
slant being scarcely noticeable. A second point is that in the Island 
specimens the malar bone is always strongly bowed downwards and 
outwards beneath the orbit (cf. also Plate 9, Fig. 1, Plate 10, Fig. 1). 
In regard to thetwo specimens figured in Plate “idk it will be observed 
that the snout region in Fig. 1 is distinctly more elongate than the 
same part in Fig. 2, with the result that, seen from above the nasals, 
more completely hide the premaxille from view in the Island than 
in the Tasmanian specimen. This feature, though it happens to be 
rather marked in the two examples fioured, is subject to a certain 
amount of variation, and cannot be relied upon. 
The two skins obtained on Flinders Island measure respectively 
715 mm. and 675 mm., the latter being slightly incomplete. The 
hind foot of the first measures 65.5 mm. In the colour and general 
nature of its fur, the larger specimen, a male, is clearly similar to 
light-coloured specimens of P. mitchelli or the Tasmanian form. In 
the smaller specimen each hair is light-coloured at the tip, giving a 
general light greyish-brown colour to the fur, the darker basal part 
of each hair being hidden from view. This basal part is much more 
darkly coloured than in the case of the other example. In the 
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