82 FOSSIL JAWS OF MACROPODID.i-:, 



Dimensions. 



Manclihtdar. — The length of the first three cheek-teeth is 66-1, 

 of the premolar 17'0, of m."^ 29*5, of p.'% mp/, m.^, m.'-^ 60-0. 

 The width of m.^ is 19-0. The anterior depth of the mandible is 

 61 '5; the thickness 33 '5. 



Maxillary. — From figure and cast. The entire length of the 

 cheek-teeth is from 11 7 '5 to 122*5, the premolar diameters 18-0 

 X 18-0, m.i m.2 are 55-5, m.-^ 31-8. The width of m.^ is from 

 20-5 to 23-1. The breadth of the palate is from 100-0 to 103-2. 



The lower molars are j)roportionately narrow, but not more so 

 than in the existing Macropods, M. (/igantens, II. agilis, and II. 

 riificollis. 



Form of teeth. 



Maxillary. — The premolar p.* (PL xiv. fig. 5) is an almost 

 regular equilateral triangle with convex sides and angles. From 

 a narrow basal rim or talon, which however seems to be restricted 

 to the inner side, the fore end of the crown slopes gently ujDwards 

 to the horizontally abraded surface of the two cusps. Of these 

 the smaller is placed over the intero-posterior angle, the larger 

 over the middle of the outer side of the base. The cusps are 

 defined by a deep indent between their posterior surfaces, anteri- 

 orly by a depression in the inclined plane in front. The posterior 

 basal talon runs from the outer angle to the middle of the hinder 

 surface of the inner cusp. Opposite the posterior indent the 

 talon is long, but behind the outer cusp where it is feebly linked 

 to the middle of the base of that cusp, short. 



Afolars. — In these as they appear in the cast the anterior basal 

 talons and their linking ridges are distinct, but in the anterior 

 teeth appear chiefly on the inner side, the posterior talons appear- 

 ing only on the outer; but on the free surface of m.^ (PI. xiv. fig. 

 6) the hinder talon is seen to extend round to the inner end of 

 the base and to send upwards a strong linking ridge towards the 

 inner end of the crest of the lol^e before it. The mesial linlcs run 

 from centre to centre of the lobes which cross the line of the 

 teeth at an oblique angle. The indications afforded by the cast 



