SUB-FOSSIL REMAINS FROM KING ISLAND 
The measurements in the first place show unmistakably that 
D. viverrinus is not represented amongst the remains. 
They equally clearly indicate the existence of a species decidedly 
larger than the existing D. maculatus, and at the same time prove 
the existence of animals of a size equal to that of large examples of 
D. maculatus. The question then arises as to whether the smaller 
King Island specimens are to be regarded as females of the larger 
form or as representatives of another species, that is D. maculatus. 
We incline to the latter opinion which, moreover, is in accordance 
with the definite statement made by Péron that two species existed 
on the island. 
A reference to Plate 8, Figs. 2 and 3, representing a larger 
and smaller specimen will serve to show how distinct the forms are, 
and though, of course, the smaller amongst the larger forms tend to 
merge iis the larger amongst the smaller, yet an examination of 
the collection as a whole unmistakably gives the impression that it 
contains the remains of two distinct torms. 
The evidence from the teeth is as decisive as that from the 
basal length of the skull, In no example of D. maculatus does the 
length of the upper first three molar teeth exceed 19°5 mm.; in 
the large island specimens it is consistently 20 mm. or more, Ca 
the same difference is seen in the length of the lower molar series 
ro) 
and of both the upper and lower pre-molar. 
But beyond these measurements there is fortunately one 
structure in the skull which both serves still further to mark the 
larger form out as a distinct species and at the same time bears 
evidence in favour of the fact that the smaller island form is 
D. maculatus. Two of the larger and two of the smaller skulls 
fortunately have the mastoid bullae sufficiently intact to show 
clearly what was its size. In D. viverrinus this is very largely 
inflated, the breadth of the bulla being at least three-quarters the 
length ; in D. maculatus the expansion of the bulla is not so great, 
the breadth being slightly more than half the length. When we 
. *. c=) 5 oa . ra . “4 - 
examine the King Island specimens (Figs. A, B, C,) we find that in 
Fic. A. Fic. B. Fie. C. 
D. bowlingi. D. maculatus. D. viverrinus. 
the large ones the bulla is decidedly more elongate and much less 
swollen, whilst in the smaller ones it is similar to that of 
D. maculatus. In a large island form with a basal length of 
[ 32 ] 
