6o] 
RECORDS OF W.A. MUSEUM. 
the outline of the perfect animal. According to one of these, the 
Marsupial Lion, unlike the other Phalangers, would have progressed 
after the manner of Kangaroos and Wallabies, and not on all fours 
as Prof. Owen had determined. Our knowledge of the animal, its 
food and habits is very incomplete, and theories concerning its life- 
history must at present be partly conjectural, but the discovery of 
a more perfect skeleton would soon definitely determine the nature 
of the creature’s food. 
The other lower incisor, besides possessing the obliquely 
truncated tip and the worn surface on the inner aspect, shows 
distinct signs of attrition on its posterior face. For a distance of 
12.6mm. near the outer edge a lenticular mass of enamel has been 
removed and a distinct hollow worn in the underlying dentine. 
Judging from the British Museum (Nat. Hist.) Cast M1958, this 
area ultimately becomes connected with the gradually increasing 
patch of dentine exposed at the worn tip. 
Of the lower functional premolars there is a fragment com- 
prising the anterior half of the enamelled crown, showing but little 
wear. Of the left mandibular P4, one tooth, still inserted in a 
fragment of the mandible, is almost perfect, the enamel coating of 
the antero-internal angle alone being absent; the two other 
fragments are the anterior and posterior halves of the enamelled 
crowns, both showing longitudinal strips of dentine where the 
enamel has been removed by attrition. 
As was the case with the other teeth described, these worn 
premolars are less than the corresponding teeth figured by Prof. 
Owen ; in this instance, the Balladonia teeth are from .72 to .8 the 
size of those from the Eastern States. 
The discovery of more abundant remains in a better state of 
preservation will, no doubt, show that the Western Australian 
Marsupial Lion was distinct from the Eastern species, Thylacoleo 
carnifex (Owen) of Victoria, and Thylacoleo oweni (McCoy) 1 of 
Queensland and New South Wales. 
Remains of Thylacoleo have not previously been recorded from 
Western Australia. 
McCoy Prod. Pal. Viet , Dec., IIP, p. 9, 1876. 
1 
