86 
FOSSIL JAWS OF MACROPODID.V 
Form. 
Maxillary. — Premolar (PL xiv. fig. 8). The anterior talon is 
well developed. Commencing about the middle of the inner side 
and passing round the fore end, where it gives off a short but 
distinct linking ridge, it extends on the outer side, but is there 
interrupted by a fracture of that side of the crown. The inner 
cusp is defined by a sharp impression on the sloping anterior 
surface, and posteriorly by a slight vertical indent between it and 
the outer cusp. The hinder surface of both cusps descends 
vertically to the low and narrow posterior talon. 
Molars. — In a slightly worn tooth exemplified by m. 1 (PI. xiv. 
fig. 7) the anterior talon is on the inner side of the fore link 
subdivided by a lofty but narrow vertical ridge; corresponding to 
this an oblique fold on the hinder surface of the fore lobe descends 
to the mid valley, making a sharp angle at its junction with the 
mid link; this again is opposed by a faint ridge on the anterior 
face of the hinder lobe, and is repeated in a similar oblique fold 
on the hinder face of the hind lobe. On the outer side of the 
latter is a very strong ridge or fold rising from the outer third of 
the basal talon to the outer end of the crest of the lobe. The 
mid valleys are closed at each end by a raised basal rim. In 
worn teeth the more or less abraded remains of the stronger of 
the several vertical folds are pretty constantly recognisable. The 
well developed talons fore and aft and the lateral basal rims give 
a quadrate, self-contained appearance to the teeth, which is 
retained to the last. 
Mandibulary. — Premolar (PI. xiv. fig. 9). The inner side of the 
fore end of the crown presents a broad groove, ending below in a 
tumid rim, simulating or representing a basal talon; the posterior 
surface of the lobe internal to the link is excavated, and the sur- 
face of wear encroached upon fore and aft is rendered narrow 
and angular, while it slopes obliquely inwards and rearwards. 
The hinder talon is long and concave on the inner side, but on 
the outer half it is nearly filled by the broad linking ridge, which 
rising upon it ascends with an inward curve upon the extero- 
posterior surface of the lobe. 
