FOSSIL JAWS OF MACROPODIDjE 



Form. 



Maxillary. — Premolar (PI. 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 b}" m. ^ (PL 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 apjDearance to the teeth, which is 

 i-etained to the last. 



Mandihulary. — -Premolar (PL 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. 



