SUB-FOSSIL REMAINS FROM KING ISLAND. 
between the dome-shaped skull of the island form and the frontally 
flattened one of the mainland form is strongly marked. It will be 
noted also that the dome shape of the cranium is indicated to a 
certain extent in the immature mainland form The frontal 
region is certainly flattened, but the proportionate height of the 
cranium above a basal line running from the condyle to the 
frontal suture is decidedly greater Apa in the mature specimens. 
There is unfortunately no derailed description of the skull of D. 
peroni available, but it the dome shape of the cranium was any- 
thing like as all marked in the Kangaroo Island species as it is 
in that of the King Island bird, it could not have failed to attract 
attention. ‘his character alone is sufficient to distinguish the 
King Island species from that of the mainland, and presumably 
also from that of Kangaroo Island. 
In the following table we give (1) certain length measurements 
of the skulls and (2) the proportionate height of the cranium to 
the length of a basal line drawn from the condyle to the frontal 
suture, taking this line as 100 :-— 
— | D. nove-hollandiz.! D. peroni. D. minor. 
=I) % ———S>S | | Vv ee 
ad ad. | juv. | 
Occiput to frontal suture... 90 91 80 80 58 | 52 58 > 
Maximum width ... Sa || zt 76 62 | 62 66 54 56 = 
Interorbital space ... sag" || 22) 32 26 26 29 | 20 aoe ” 
Length of premaxilla 84 70+) 74 | 74 ee eer Ue 20 
Proportionate height of skull 39 38 40 | ce 43 | . | 2 ao 
6. Pectoral Arch. 
(Plate 4. Figures 19 and 20.) 
Only one pectoral arch—that of the right side—has been 
found, and that has the clavicle missing, and about half of the 
scapular broken off. It is not perfect enough to found any com- 
parisons upon. 
Portions of three Sterna. 
(Plate 7.) 
It was found very difficult to secure remains of the sterna» 
which broke up into powder as soon as they were touched. 
The fragment figured represents the greater part of it, but 
there is nothing apart from size to distinguish it clearly from 
the sternum of the mainland bird. The concavity on the 
inner or upper side is less accentuated, but then this is a 
feature in which the mainland form varies: one of our specimens 
being decidedly shallower and flatter than the one figured. The 
difference in size is, however, striking. 
[ 16 ] 
