234 
PROFESSOR OWEN ON THE FOSSIL MAMMALS OF AUSTRALIA . 
The fact is patent ; but the inference has been called in question. 
Dr. Falconer writes, in June 1862, “Next, as regards the depressed position of the 
condyle — below the level of the grinding-teeth. The author of ‘Palaeontology’ states 
that it is ‘ a character unknown among any herbivorous or mixed-feeding animal.’ I 
again refer my reader to the figure (pi. 34. fig. 13) of the lower jaw of the Aye-aye”*. 
This figure is essentially the same as that in my Memoir read before the Zoological 
Society, January 14th, 1862 (fig. 9). Prior to that date the depressed position of the 
condyle to the level of the grinding-teeth (fig. 9, b) was a character unknown in any 
herbivorous or mixed-feeding animal ; it is still so unknown as depressed below that 
level, such as we see it in Plagiaulax (fig. 10). Dr. Falconer, proceeding with his evi- 
Fig. 9. 
Mandible of Chiromys Madagascariensis, natural 
size (Zool. Trans, vol. v. pi. 20. fig. 9, Memoir of 
January 14, 1862). 
Fig. 10. 
C 
Mandible of ■' Plagiaulax Becldesii, magnified four 
diameters” (after Falconer, XI. pi. 34. fig. 1). 
dence of the herbivority of the gnawing Lemur and his comparison of its mandible with 
that of Plagiaulax, admits that “ the condyle looks still more depressed in Plagiaulax 
Pecklesii ; but this is, in part, owing to the inflected margin of the angle being broken 
off in the fossil, while it is entire and salient in the recent form, thus elevating the con- 
dyle above the lower plane of the ramus, and leading to an appearance of a greater 
amount of difference than exists in nature’ f. 
Here we are at issue on a matter of fact. I affirm that the condyle (b, fig. 10) in Plagi- 
aulax would not be so elevated above the lower plane of the ramus if the angle ( a , fig. 10) 
were entire and salient, because the saliency has an inward, not a downward, direc- 
tion. The correspondence in this respect, as well as in the low position of condyle, of 
Plagiaulax with the carnivorous Thylacoleo, Dasyures, and Thylacines, and its difference 
from the herbivorous marsupials (fig. 6) and larvivorous Lemur (fig. 9) is as clearly 
demonstrated in the Purbeck fossils, as if the inflected angle had received no fracture 
whatever. 
For other differences of mandibular structure and configuration between Plagiaulax 
and Chiromys, invalidating Dr. Falconer’s argument in favour of a common herbivorous 
or rodent nature associated with a common depressed position of condyle, I refer to figs. 
9 & 10. 
In reference to the subject of the latter illustration, Dr. Falconer has remarked, “ Pro- 
* X. p. 361 ; XI. p. 445. t X. p. 361 ; XI. p. 446. 
