BY C. W. DE VIS. 
115 
living species; by the greater width of the molars, that of m. 3 
averaging 7 1 against 6*4 in II. agilis; by its much feebler inter- 
lobular links; and by the straightness of the lower edge of the 
mandible. The same characters serve to separate it from //. 
ualabatus, which approaches it somewhat more nearly in the 
length of the premolar, but recedes further from it in the total 
length of the cheek-teeth. With no other recent species is it 
comparable as to the dimensions of teeth, though in the depth 
and thickness of the mandible it is occasionally exceeded by all 
the larger-sized modern wallabies. 
Form. 
Mandibular. — P. 4 (PL xvn. fig. 3) subelongate, oblong, cuneiform, 
diameters 9 6 x 4*4, sides parallel, fore end obtusely pointed. 
Crest a little to the inner side, with obtuse denticulations corres- 
ponding to coarse but indistinct corrugations on either side of the 
mesially compressed crown. A faintly marked nodular basal rim 
on either side is continuous round the fore end. In a second 
example with diameters 9-2 x 4 -6 the mesial compression of the 
crown is stronger, and the crest curves slightly over to the intero- 
posterior angle, rendering the inner side of that end of the crown 
subconchoidal. Length equal to or rather less than that of m. 4 . 
Mandible elongate, shallow, nearly straight from the posterior 
molar forward. 
Molars (PI. xvn. fig. 4) without accessory folds; with or without 
a rudimentary talon; links narrow and low. 
Persistence of teeth. 
The permanent premolar though much worn is still in the 
horizontal line of the molars, and shows no sign of ejection when 
the last molar has been some time in use; in another instance the 
roots of the broken tooth are in place, though m. 4 is much worn. 
Examples — sixteen. 
These consist of two adult mandibular rami with all the cheek- 
teeth, the premolar of one of them being imperfect; of three with 
