109 



yet, though faintly shown, they may be recognized at e and/ in tig. 1. In the great 

 extinct Cave Lion of Europe {Felis spelcea, fig. 3, between 1 & 2, Plate VI.), the 

 sectorial, with a similar divergence of the two roots for firmer implantation of the tooth, 

 shows less excess of size of the hinder root ; the crown is more definitely divided than in 

 the Hyana into three lobes ; and part of the middle and more prominent one, as well as 

 the anterior lobe, is supported by the long, thick though smaller anterior root. But the 

 inner enlargement fig. 4) of the fore lobe more resembles that marked t in fig. 3 (of 

 the second row) in being a tubercle, than it is in the Hyana (fig. 5, t) ; and, so far, 

 figs. 3 & 4 indicate a more strictly flesh-feeding animal than fig. 5. The close corre- 

 spondence, however, of the line or direction of wear, the polished smoothness interrupted 

 by a few distant vertical linear risings in figs. 3 & 5, indicated a similarity of the 

 substances to be operated upon and identity in the mode of mastication, exercised by the 

 Hyana and the great Australian Carnivore. 



The vertically worn surface in Felis (fig. 4) is less even or continuous, being inter- 

 rupted by angular projections, the chief of which (y, fig. 4) answers to the less developed 

 one (y, fig. 5), which has no corresponding one in fig. 3. The tubercle (t) in Hyana, 

 however, distinguishes it more essentially from the Australian fossil (fig. 3) ; while the 

 feeble rudiment of that enlargement in the genus Machairodus (figs. 7, 8, t) makes this 

 extinct European Feline approach nearest in carnassiality to the Thjlacoleo. The demon- 

 stration, in short, of the carnivorous character of the Queensland fossils, and consequently of 

 the problematical Cave-fossils, was so plain and complete at the close of the comparisons, 

 of which the most essential are illustrated in PI. VI., that the only doubt engendered 

 was as to whether the Australian carnassial and tubercular teeth belonged to a marsupial 

 or to a placental extinct form of Carnivore. But the degree in which the subjects of 

 figs. 1, 9, 10, 12 exceed in the size and carnassiality of the sectorial tooth, justified the 

 inference of the more ferocious and flesh-feeding habits of the Australiau Carnivore. 



DESCRIPTION OF THE PLATE. 

 PLATE VI. 



Fig. 1. Outer side view of a portion of a right superior maxillary bone, with the sectorial 



molar tooth of Thylacolco carnifex, Ow. 

 Fig. 2. Outer side view of the corresponding part and tooth of the great extinct Hycena 



{Hycena spelcea, Goldfuss). 

 Fig. 3 (upper row). Outer side view of the upper sectorial molar, in a fragment of 



the superior maxillary bone of the great extinct British Lion (Felis spelcea, 



Goldfuss). 



Fig. 6 (3 bis, second row). Inner side view of the sectorial and tubercular molars of 

 fig. 1 [Thylacoleo carnifex). 



