180 
PROFESSOR OWEN ON THE FOSSIL MAMMALS OF AUSTRALIA. 
differs from Phascolomys latifrons (Woodcut, fig. 8, b), in which the postpalatal apertures 
extend forward beyond, or at least as far as, the interval between the last and penulti- 
mate sockets*. In the more advanced portion of the roof of the mouth I noticed (in 
1845) a character^ in Pliascolomys latifrons by which it differed from Phase, vombatus , 
and as I now know it also differs from Phase . platyrhinus. The portion of bony palate 
Eig'. 7 . 
Fig. 8 . 
Palatal surface of upper jaw and teeth, 
Phascolomys platyrhinus : nat. size. 
Palatal surface of upper jaw and teeth, 
Phascolomys latifrons : nat. size. 
between the molary series and the incisors is more concave transversely, or deeper, in 
Phascolomys latifrons (Woodcut, fig. 8 , 21, 21', 22, 22), and the channel is hounded by well- 
defined or sharp borders : this character is much better marked in the fossil (Plate XVII. 
fig. 5 , 2i', 21', 22, 22) than in the skulls of Phascolomys vombatus or Phase, yflatyrhinus. 
Another character in which the fossil resembles Phascolomys latifrons more than it 
* In the latter variety (fig. 8 ) the apertures should extend more forward than is represented, 
t Trans. Zool. Soc. vol. ii. plate lxxi. fig. 1 . “ The palatal surface of the intcrmaxillaries is deeper” (p. 304 ). 
