PROFESSOR OWEN ON THE FOSSIL MAMMALS OF AUSTRALIA. 
265 
Fig. 2. Fore part of mandibular ramus, showing depth of implantation of laniary ( i ), 
and part of socket of carnassial ( p 4) ; from a “ photograph.” (Id. ib.) 
Fig. 3. Front view of mandible and teeth ; the bone in outline : from original fossils. 
Fig. 4. Right lower incisor, inner side view ; from a “ photograph.” (Original, a cave- 
specimen in the Museum of Natural History, Sydney, New South Wales.) 
Fig. 5. Right lower incisor, from a breccia-cave in Wellington Valley, outer side view. 
Fig. 6 . Right lower incisor, from a breccia-cave in Wellington Valley, inner side view. 
Fig. 7. Right lower incisor, from a breccia-cave in Wellington Valley, back view. 
Fig. 8 . Right lower incisor, from a breccia-cave in Wellington Valley, transverse section, 
one-third from apex of crown. 
Fig. 9. Right lower incisor, from a breccia-cave in Wellington Valley, transverse section 
of base of crown. 
The subjects of the foregoing figures are from Thylacoleo carnifex , nat. size. 
Fig. 10. Left mandibular ramus and teeth, Bettongia , nat. size. 
Fig. 11. Inner side view of a sheathed ungual phalanx (claw-core exposed by the re- 
moval of part of bony sheath) of an unguiculate mammal. 
Fig. 12. Outer side view of a similar ungual phalanx, with more of the bony sheath 
preserved. 
Fig. 13. Side view of a similar ungual phalanx; sheath mutilated. 
Fig. 14. Under view of the same phalanx. 
(From “photographs:” the originals in the Museum of Natural History, 
Sydney, New South Wales, were obtained from the same breccia as the 
subjects of figs. 1 and 2 , and are from a large carnivore, probably of the 
same species.) 
PLATE XIV. 
Section of the skull of Thylacoleo carnifex as at present known, showing the 
cerebral cavity and the entire dentition from nature, nat. size. Owing 
to the crowding of the abortive premolars (p 1 , 2 , 3 ) to the inner side of 
the functional one (^ 4 ), a complete view of the dental system cannot be 
had from the outer side of the jaws: if illustrated from that point of 
view it must be more or less diagrammatically ; this Plate is, therefore, 
added, to be contrasted, as to number and relative size and position of 
the teeth, with the restorations which have been published in support of 
the herbivorous hypothesis of Thylacoleo. I have refrained from com- 
pleting anatomically the articular part and ascending ramus of the man- 
dible : one cannot doubt but that, ere long, an entire mandibular ramus of 
Thylacoleo carnifex will be obtained. The section of the cerebral cavity 
confirms the ascription of the extinct carnivore to the Lyencephalous 
subclass. The cerebellum, as in Basyurus , rises wholly behind the 
