244 
PHASCOLOMYID-E. 
molar of each series, which is a premolar, as is often the case 
with the premolar teeth, represents one half of a true molar ; 
in the lower jaw it is nearly cylindrical, and in the upper jaw 
it differs in having a small anterior lobe. The two rows of 
molar teeth of either jaw converge in front, so that they are 
there separated but by a narrow space, especially those of the 
upper jaw. A more perfect idea of the structure of the teeth 
of the Wombat will be obtained upon referring to 
PLATE 3. 
i. t. Figs. 1. Are the incisor teeth. 
p —r/i. The premolars. 
Fig. 1 b . Is the masticating surface of a true molar. 
Fig. 1 c. Represents the same tooth, viewed from the inner side, and 
Fig. 1 d. Is the same, viewed from behind. 
Fossil remains of a Wombat have been found in the caves 
of Wellington Valley, approaching very near to the recent 
species ; but after a minute comparison of a considerable por¬ 
tion of a cranium and lower jaw, procured by Sir Thomas 
Mitchell in the caves mentioned, with the corresponding parts 
of the recent Wombat, Professor Owen found some differences 
in the proportions of the teeth which induced him to regard 
the fossil species ns distinct, and in Sir Thomas Mitchells 
work, 1 the Professor proposes for it the name. 
Phascolomys Mitcliellii (fossil.) 
“ In this species,” Professor Owen observes, “ the molar 
teeth have the antero-posterior diameter greater in proportion 
to the transverse; as compared with the molars of Ph. Womlut; 
1 Three Expeditions into the Interior of Australia, &c. p. 308, IM. 18. 
